Home

Film & Digital Techniques for Zone System Photography

Contents

1. 0 000 9 Controlling Variables 0 0000 10 Aperture and Shutter Speed Calibration 10 Film Speed Test sv tadedosncy bene ean ao oh 10 2 UNDERSTANDING LIGHT 19 Color and Tonality 0 000 21 Seeing the Scene Human Vision vs Photography 23 Qualities of Light serer cerei paesini ei a 25 Reflected Light 54 604 sects a eee coves an 25 Specular vs Diffuse Light 27 Sweet Light ihe sauna reo wie saaae 28 3 THE ZONE SCALE 29 Dark Zones 0 I II 2205 30 Zone 0 Black 0 eee eee ee ees 30 Zone I Near Black 00 31 Zone II Patterned Darkness 31 Detail Zones Zones III IV V VI and VII 32 Zone III Shadow Detail 32 Zone IV Dark Middle Gray 32 Zone V Middle Gray 00 32 Zone VI Light Middle Gray 34 CONTENTS Zone VII Highlight Detail 34 Highlight Zones Zones VIII IX and X 35 Zone VIII Patterned Highlight 35 Zone IX Near White 36 Zone X White sanami guesa ias ee tiise 36 4 ZONE PLACEMENT 39 The Law of Reciprocity 0004 39 The Characteristic Curve 004 40 The Paper Curve vecer gues eed eae ceda 40 The Pilm Curve i ssc 8aiwe ae amni seine wi ed 40 Placing the Zones 0 0
2. in or out this is not recommended because of the intermittency effect cre ated by making multiple exposures This will change the zone concept of the exposure needed in the film To determine developing times for the Zone System start with the manu facturer s normal developing time Then develop four pieces of film with an additional 10 percent and 20 percent more time with two other develop ments at 7 percent and 14 percent less time This will give you five pieces of film providing a good spread in your curves DEVELOPMENT 57 Once you have processed the five pieces of film at the different times you must read them on a transmission densitometer In this case you read and record each step on the film Some may be only B F but you need to read all steps You will have a series of density numbers Plot all the film on the same graph but plot each film separately It is suggested that you use various colors for each curve Once again we use the vertical axis to plot the density value from your densitometer readings and the horizontal axis is used to plot the steps of the step wedge Find Dmin on the steepest and shallowest curve Just as in paper Dmin is FB F 0 04 Next connect these two points to form a line that represents Dmin on all curves This line might be at an angle sloping slightly downward or may be horizontal To establish Dmax you will add the exposure range for the paper to the value of Dmin This is called fit
3. Photos by Christopher Broughton The accent ability of Zone X is the important concern in the picture Like black too much white can harm the effectiveness of an image When there is a great deal of white a void will be formed and or the photo will have a hot look If borders are important to the function of the photo white at the edge of the image will break up or diminish the structural concept of the border Pure base white is easy to lose as you produce and finish your prints Safe lights can fog the paper slightly overwashing can reduce the baryta coating and chemical staining incomplete fixing and dry down of fiber papers will all contribute to a loss of the dynamic range from the white part of the print THE IDEA OF EQUIVALENT EXPOSURES ONLY WORKS BECAUSE OF RECIPROCITY Facing page Photo by David Ruderman CHAPTER FOUR ZONE PLACEMENT Imagine for a moment that you wish to photograph a light skinned woman You meter her skin and get a recommended exposure of 8 at 30 second However this exposure will render your subject s skin tones as Zone V middle gray Obviously this would be too dark for your fair skinned subject Fortunately there is a remedy for this situation For now simply note that in creasing the exposure will get you closer to your goal of creating a more re alistic rendering of your subject Note too that in order to do this you ll need to practice a technique referred to as zone
4. ent or gamma depending on the shape of the curve and measurement method Note that Zone 0 from the scene will fall at and below Dmin of the film As discussed earlier Zone I falls at the speed point or the begin ning of the straight line This means Zone 0 and Zone I will not work well Shoulder HE zi IE L Dmax rt hel E HEHA B a i ia Ps HE HH HH Cmim EERE u se a JE aT ELI a4 a 11 2i Top The paper curve is steep with a pronounced toe and shoulder The red line is the curve rep resenting the densities measured from a series of tones printed on the paper The top blue line represents Dmax and the lower blue line is Dmin The zone scale at the right shows where the var ious zones will print in relation to the curve Above The film curve is not as steep as the paper curve with a less pronounced toe and shoulder The red line is the curve representing the densities measured from a series of tones produced on film The top blue line represents Dmax and the lower blue line is Dmin The zone scale at the right shows where the various zones will be captured in relation to the curve The zones are shown as they represent the scene and the print 40 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Christopher Broughton AS THE EXPOSURE INCREASES A CORRESPONDING CHANGE IN DENSITY OCCURS within a predictable linear relationship While t
5. shows the developer dilution recommendations for Kodak Tmax at a consis tent developing time With this in mind we can take our information about the relationship of light development and the paper into the field to make the Zone System work When in the field you need only two parts of the equation the N val ues and effective ISOs However you will also need to remember what light condition or for what N development each roll or sheet of film has been ex posed You might consider taking minimal notes on the exposed roll or cut sheet film holder for reference when you return to the darkroom KODAK TMAX 100 400 ILFORD DELTA 100 KODAK TMAX 100 400 SELECTED DENSITY RANGE 1 0 SELECTED DENSITY RANGE 1 0 SELECTED DENSITY RANGE 1 0 DEVELOPER D 76 1 1 AT 70 F DEVELOPER D 76 1 1 AT 70 F DEVELOPER HC 110 70 F FOR X MINUTES N Dev Dev Time Effective ISO N Dev Dev Time Effective ISO N 1 7 N 3 15 200 800 N 3 17 est 160 N 1 2 7 N 2 121 2 125 250 N 2 12 125 N 2 4 7 N 1 10 100 400 N 1 8 100 N 3 8 7 N 87 4 80 320 N 61 2 80 N 1 8 80 320 N 1 53 4 64 N 2 71 2 64 250 N 2 5 64 N 3 67 4 50 200 N 3 41 2 50 N 4 6 50 200 N 4 33 4 NR 50 64 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY CHAPTER SEVEN MAKING PHOTOGRAPHS Having generated the information required for the Zone System you can go into the field to make photographs You can previsualize your prints while ob
6. 0 2 and the other is high contrast 4 5 then the resultant print will have the highlight characteristic of the low con trast filter with the dark shadow areas looking like the printing from the higher contrast filter This technique will give the print sharpened shadow and highlight details LOCAL CONTROL Very early in our photographic education we learned to dodge and burn in the printing process However it is difficult to know how much dodging or burning to apply at various areas in one print This is particularly true when the print requires both dodging and burning To best make these determi nations you can create mini prints of areas that require dodging or burning Facing page Photo by Glenn Rand Right Photo by Glenn Rand START BY MAKING A PRINT WITH A BASE EXPOSURE TIME AND NO DODGING OR BURNING N 4 then lay them on the working print to show the amount of dodge or burn that will be applied in those areas Because the mini prints can be changed and compared directly to the working print there is no need to reprint the work ing print with each change Start by making a print with a base exposure time and no dodging or burn ing This print should show the proper overall contrast If you are tray print ing then after at least half the time needed for total fixing the print should be squeegeed on a viewing board Next you make judgments on the test prints to determine how much dodgi
7. 1 can be used Very small amounts of light are used to make the test strip It is important to know how many exposures TO INCREASE THE EFFECT OF are made This is important since you are trying to build up exposure that FLASHING ALOWER NUMBER does not gray the paper Once the paper is processed you determine the flashing exposure by taking the last exposure time that does not show on the FILTER 0 1 CAN BE USED test strip Ifall your steps show a gray difference compared to the paper base you will need to repeat the process at a lower exposure level by shortening your base time or stopping down BLEACHING Bleaching photographs is not the same as whitening clothes In the photo graphic process development changes exposed silver halide crystals into black metallic silver Potassium ferricyanide the active agent in photographic Photo by David Ruderman Photo by Glenn Rand BLEACHING CAN BE USED ON THE IMAGE GLOBALLY ORAS A LOCAL CONTROL a Si th 2 ee ee ah F a z bleaching changes developed metallic silvers back to a silver halide form Normally potassium bromide is added to the solution Bringing the devel oped silver back to a form similar to silver halide means that fixer will dissolve bleached areas of a print Bleaching can be done in a two step process using potassium ferricyanide followed by fixer or by using Farmer s Reducer which has both the bleach and fixer in one solu
8. If you are unsure consult the user s manual Here are the specific steps for conducting the film speed test 1 With your camera in manual mode and the lens focused at infinity ex pose two frames with the lens cap on 2 Next remove the lens cap and prepare to photograph the target 3 Set your meter s or camera s ISO to 4 the ISO rating of the film For example if you re using ISO 100 film set your camera or meter to ISO 25 if you re using 400 speed film set it to ISO 100 16 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Christopher Broughton DO NOT CONDUCT THE TEST ON A DAY WHEN THE SUN IS INTERMITTENTLY BLOCKED BY CLOUD COVER RESET YOUR CAMERA S ISO SETTING TO MATCH THE FILM S PRINTED ISO RATING AND FINISH THE ROLL Photo by Glenn Rand Meter the dark part of the target you have set up Note There is no need to re meter before capturing subsequent frames Stop down four full stops from your metered reading In other words if your meter reading was f 5 6 at As second your new exposure would be 5 6 at 50 second or an equivalent exposure Use the largest aper ture smallest f stop number as your starting lens setting Focus at in finity and fill the frame with the target The card need not be in focus Make an exposure of the target Stop down your aperture using the smallest increment e g 1 3 or 1 2 stop available and capture another
9. Since the Zone System works by using the development of the film to control the amount of light reaching the paper we will want to use the paper s exposure range value as the difference be 58 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Glenn Rand tween Dmin and Dmax This means that the light from the scene that rep resents white for the negative will be Dmax in the negative Once again you define your limits on the extremes by finding Dmax on Photo by Christopher Broughton only the steepest and shallowest curve If the shallowest curve does not rise to a density level high enough to add the exposure range of the paper to its Dmin and be on the line then extend the line on the angle suggested by the curve This shows that the film requires much more exposure to achieve Dmax than was available in your test This situation is not unusual for short development times As with Dmin you connect the two extremes with a straight line This will cross the other curves and define their Dmaxes Working with each curve separately draw vertical lines down from where the Dmin and Dmax lines cross each curve This establishes the exposure range for the film for the amount of development expressed in that curve Count the number of steps between the two vertical lines you created then divide by two if you used a 0 15 step wedge or by three if you used a 0 10 step wedge to make the test negatives The res
10. a metronome from a musical instrument store FILTER DODGING AND BURNING To dodge and burn your prints you can use multi contrast printing filters in stead of solid tools Using a filter allows you to see the area you are dodging not just a moving shadow You also have the option to change the contrast in the dodged area if you are using multigrade paper This method is the sim plest and easiest way to change contrast within an image By using a magenta filter 4 5 as you dodge you also increase the contrast in the area that is USING A FILTER ALLOWS YOU TO SEE THE AREA YOU ARE DODGING NOT JUST A MOVING SHADOW Selective contrast dodging increased the con trast of the waterfall compared to the rocks A piece of 4 multi contrast filter was cut to cre ate a custom shaped dodging tool This not only reduced the light reaching the waterfall area of the print but raised its contrast within making it sparkle Photo by Glenn Rand Photo by Christopher Broughton THIS PREEXPOSURE PROCESS IS MORE COMMON IN PRINTING AND IS KNOWN AS FLASHING dodged This adds more brilliance to lighter tones in the dodged area You can also use a neutral density filter if only lightening is desired without a change in contrast If you wish to use a contrast filter when burning a highlight area of the print select a yellow filter 0 1 for use in combination with your burning tool The lower contrast filter used for burning adds
11. aspects of the photographic process development and printing however are either dependent variables we can control how they change or constants they don t change By controlling the dependent variables in the photographic system we can compensate for the effect of the constants and the independent variables GETTING STARTED 9 CONTROLLING VARIABLES Aperture and Shutter Speed Calibration Shutter speed calibration is the first step in standardizing our photographic process If a spring mechanism creates the shutter speeds the speeds may vary based on the strength age and reliability of the spring and this introduces an unwanted variable into our imaging Use a shutter speed tester or go to a camera repair shop to have the lens tested Unless the shutter speeds are far out of line more than a fac tor of s stop the known variation can be added into the exposure calcula tion If there is a significant or inconsistent difference between the marked and actual speeds the lens or shutter system should be repaired The aperture settings on most cameras click into position to ensure that the manufacturer s setting is maintained If this is sloppy have your lens checked at a camera repair shop Film Speed Test Another important step in preparing to use the Zone System is the film speed test Conducting the test will allow you to ensure that the ISO setting on your camera is matched to the published ISO rating of you
12. lt 4 stopping down two stops from the light meter reading just taken for Zone III After stop ping down an exposure is made With these five steps you have made an exposure with the development of the film in mind Based on the testing the development will be at the calculated time N determined in step 2 Using this system it should be quite simple When metering you should always isolate the tonal areas that will become the overall or chosen zones of your photograph Without a spot meter we often find that we cannot get sufficiently close to the actual subject of the scene to meter the zones In this case you can meter a nearby object that is similar in tone to your intended subject If you use this approach be sure the light meter is positioned at an angle to the surrogate tone that approximates the angle of the camera to the scene Also realize that like the exposure itself metering is subject to flare If your meter is pointed at or near a bright ob ject or light source the flare in the metering will increase Let us look at the two methods you turn to when using the Zone System to make exposures 68 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Glenn Rand ALSO REALIZE THAT LIKE THE EXPOSURE ITSELF METERING IS SUBJECT TO FLARE THIS METHOD HOLDS THE LIGHT AS UNCHANGING DURING THE PHOTOGRAPHY SESSION Right Mijas Spain 1992 1 Darkest tone meter reading f 2 2 Brightest to
13. s plane the back of the camera Also ensure that you can see part of the white fabric with detail 3 Check to see that the light is non directional 1 e diffuse on the model and card s Do not conduct the test under specular light 4 The ISO for the light meter must be the same as the selected ISO for the camera Because of noise considerations it is recommended that you use ISO 100 or the lowest available ISO for baseline testing 5 Take an incident meter reading and write down the f stop and shutter speed 6 Take a reflective meter reading of the white test patch Subtract the inci dent reading step 5 from the reflected white reading The resulting value will be used when determining the optimal exposure 7 Make an exposure with the aperture opened up two stops from the read ing obtained in step 5 8 Close down the lens 3 stop and take your second exposure If your lens has Y2 stops do the test in 1 2 stops Record the information obtained for each successive frame THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY 113 9 Close down another fs stop or 1 2 stop if appropriate and take another exposure Repeat until you have a complete four stop range To determine your camera s true ISO read the white card with the color sampler tool in your image editing software Neutralize the file then take a series of readings across the white card The neutralizing should not include adjusting the white point The correct expos
14. the paper is more rigid than a multi contrast paper it does allow for some flexibility The amount of development will change the contrast function of the paper Photographic paper develops to completion Completion means that the density of the paper increases to a certain level and no amount of develop ment will make it darker Therefore if we change the development we still can reach completion and maintain our black density Since we are trying to reach a point of completion we can change the time temperature or strength of the chemistry and still achieve total development As with film overdevelopment changes the angle of the straight line por tion of the paper curve As you overdevelop you compact the exposure range of the paper This is the same as increasing the grade or number of the filter While high strength developers will create this difference so will the increase of development time Unlike film there is not as much latitude in developing paper and we can gain only s to 4 grade through overdevelopment This ADVANCED PRINTING TECHNIQUES 93 eget means that through simply overdeveloping your paper you can make a grade 2 paper print like a 21 It also means that if you are using multigrade fiber based paper with printing filters and tray processing you can increase your de veloping time slightly and have continuous variability in the contrast of the paper Like increasing the development time of the paper weakenin
15. 0 0 0 eee eee 4 Alternative Metering Methods 42 Dark Tone Metering 43 Highlight Detail Metering 43 Average Value Metering 44 5 VISUALIZING THE SYSTEM 45 ei a ee eer ee ee oe ee rere 45 Camera System Flare 45 Scenic Flare sga caw daddies vas bene ned 46 Tonal Relationships e seure merania n 48 Expansion Compaction 49 6 DEVELOPMENT ooon 53 The Papet 954 0xnd edi Vee cei ey ake 53 AU 43a axe heen adh Krein manda 56 Plotting Film Curves 04 56 Exactness of Development 64 CONTENTS 3 Photo by David Ruderman 7 MAKING PHOTOGRAPHS 65 Zone Control as an Overall Concept 69 Zone Control as a Tonal Separation Concept 72 Incident Metering 000 0 76 Field CGE tS une n n ie OR OR Te 76 8 IN CAMERA CONTRAST CORRECTION 79 Filters drece ane Ge bk hs wart hoes dado a be 79 Dodging Exposure s isara si ue a t e pis ea 83 PreexpOs r oieee 44 eu E eas by e 85 Reciprocity Failure Compensation 87 Using Reciprocity Failure for Expansion 89 9 ADVANCED PRINTING TECHNIQUES 93 Global Controls 002000000 93 Development Control 00 0 93 Multi Contrast Printing 0 97 Local Control s22ec sa5 seen d Wis eee es 97 Filter Dodging and Burning 100 Flashing
16. FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY I PREVISUALIZED THE PICTURE AS HAVING A BRIGHT BUSH AGAINST DARK ROCKS Right Canyonlands N P 1996 1 Zone VIII meter reading f 11 2 Zone III reading f 4 3 Area metered for exposure as Zone III Photo by Glenn Rand Below This image shows the effect of the N 2 development on the scene s tone fb if Til YI YII ii w E mu ee Pre a Os ET Pe 2 ee Example 2 The scene was characterized by bright sun on red rocks with medium green bush I previsualized the picture as having a bright bush against dark rocks How ever when I metered the bright highlight that I wanted to present as Zone VIII I found there was just three stops difference from the area of the scene I wanted to be Zone II Even with bright specular light I found I needed to overdevelop to spread the density in the negative to represent these areas as Zone VIII and Zone III in the print This is because the tonal separation was smaller than the zone spread desired Here s how it was done 1 Determine the light There was a five stop range in the image I previsual ized Zone VIII Zone III However the reading f 4 and f 11 showed a three stop difference between the highlights and shadows 2 Calculate the development Determined Zone Difference Metered Zones Development 5 3 2 Therefore the development was N 2 3 Adjust the ISO ISO 1
17. In the following pages you will read descriptions of the eleven zones The scale can be thought of as being comprised of three separate areas the dark This illustration shows the way a black white zones detail zones and highlight zones The dark zones add richness to the gradient is divided into zones Filmand print They do not support detail but do provide dark patterns The detail el gal pa oak ions the high and low ones are the information carriers for the picture The highlight zones pro responses to tones in the scene and thus the zones will enlarge as they move toward either Vide sparkle and life to the picture The way the dark zones and highlight end of the gradient of black to white tones zones interact determines the tonal range and dynamism of the print Sy ey as ras Wa 1a 17a THE ZONE SCALE 29 You will also find a discussion of the qualities the various tones add to the image These are 1 pattern observable tonal shifts without image information 2 soft detail image information at a low level of commu nication 3 texture a repetitive change in image tone with reasonable sharpness and 4 sharp detail a quality that provides strong image in formation allowing easier reading of the subject While we talk about the way the zones look or are previsualized we will also discuss how they relate to the measurement of density in the print or negative where appropriate DARK ZONES ZONE
18. K al a C Me i Hi ur L Lal La L3 La LL LE oa on a oil os Ba oa oa at os AN ALLELE AAT ATT UTA ET Pee eee ALT 56 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY So ee a a vani ee Paa a are nD 4 T T a ale gt ws es W LI gt A Th F z ee i i m amn ag 4 _ F o AN Photo by Christopher Broughton second choice A camera can also be used By photographing an evenly toned board and adjusting the exposure of each frame a series of tonal steps can be created The range of tones needed to plot the characteristic curves must in clude tonal values from five stops under the meter reading for the board to at least seven stops over the meter reading This will give you a twelve stop brightness range Ifyou are using sheet film the same process can be used but it will require a lot of film To save film and simplify the processing you can create dark slides and only part of the film will be exposed during any exposure A dark slide with a hole cut in one quadrant will allow two exposures by turning the slide over between exposures If another dark slide is modified with the hole TO SAVE FILM AND SIMPLIFY cutin the other end of the slide you will have the ability to accomplish four THE PROCESSING YOU CAN CREATE POSures on each sheet of film While it might be attractive to use the dark slide to move small increments DARK SLIDES
19. Metered Light Develop ment 7 6 1 Therefore the development was N 1 3 Adjust the ISO ISO 100 was entered into the light meter Expose for the shadow detail I took a meter reading at the area I wanted IN THE SCENE THAN THE FILM WAS CAPABLE OF PRESENTING nN to represent as Zone III in the print 5 Set the exposure I stopped down two stops from the exposure reading obtained in step 4 and made the exposure Processing the film upon return to the darkroom I used D 76 1 1 for 10 minutes at 70 F This exposure and processing allowed me to adjust the tonalities of the scene by expanding the tonal values That developed the highlights with more density to fit the exposure range of the paper This negative was now print MAKING PHOTOGRAPHS 71 able without becoming muddy In metering I learned there was one stop less dynamic range in the scene than the film would normally handle Note that having determined this exposure development relationship it could be used for the rest of the roll as long as the light and subject s openness to the sky stayed the same ZONE CONTROL AS A TONAL SEPARATION CONCEPT When you are using sheet film or can work with one exposure at a time using a tonal separation concept provides the ultimate control of black amp white photography Tonal separation exposure with zone placement is what most photographers call the Zone System The method works with scene specific situations The t
20. Photo by Glenn Rand the highlights into an overexposed situation it would be better to deal with the tonal placement in the processing software Unlike film digital capture holds this f stop zone relationship across its entire capture range This is be cause the way film exposes and is processed creates an S shaped characteris tic curve while digital produces a straight line throughout its image range THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY 117 However digital capture ends abruptly at its white and noise limits while film continues beyond the f stop zone relationship Our second consideration is the predetermination of development for the negative based on light conditions within the scene When working with a film based system the development becomes our N value Within a digital based system we only need to determine how we wish to move the exposure with our consideration of not overexposing the highlights USING THE DIGITAL SYSTEM When applying the Zone System in digital photography we must use an over all approach adapting the light environment to the capture potentials We will have the ability to move zones within the capture and imaging software but for exposure an overall approach performs best Because we will need to deal with highlights and do not have the ability to use overexposed areas in our final output we will adjust the high end of the image in exposure and use imaging software to adjust other areas within the
21. are a bright sun and dry atmosphere with the white washed buildings as the subject To create this image I looked at the overall scene and chose as the dark est point the dark part of the flag When I metered that area with a spot meter I got a reading of f 2 The highlight reading was f 32 This meant that the darkest and lightest areas were eight stops apart and there was more dynamic range in the scene than the film would deem normal Therefore the de velopment was compacted to bring the highlights into the paper s exposure range Here s how it was done 1 Determine the light Normal light has a seven stop range The metered light in the scene ranged from f 2 to 32 or nine stops 2 Calculate the development Normal Light Metered Light Develop ment 7 9 2 Therefore the development was N 2 3 Adjust the ISO ISO 64 was entered into the light meter 4 Expose for the shadow detail I took a meter reading at the area I wanted to represent as Zone III in the print 5 Set the exposure I stopped down two stops from the exposure reading obtained in step 4 and made the exposure Processing the film upon return to the darkroom I used D 76 1 1 for 71 minutes at 70 F This exposure and processing allowed me to adjust the tonalities of the scene by compaction This brought the highlights down to a density range in the negative that was printable meaning no burning or flashing was nec
22. calculated YOU SHOULD HAVE A NUMBER THAT IS IN THE ANSI RANGE FOR YOUR GRADE OR FILTER and how they relate to the zones and plot a horizontal line on our graph at the value of Dmin we will establish the point we need for finding the exposure range i e exposure index of the paper Using the highest density reading you should have at least three steps at this value we calculate Dmax The highest reading is known as maximum black To find Dmax you multiply maximum black by 0 90 Again we draw a horizontal line this time using the value of Dmax and where it crosses our curve we establish the point we will need for finding the exposure range of the paper From these two points on the curve we then draw vertical lines down through the base of the graph These lines represent the limits of the paper s exposure range The exposure range exposure index is determined by counting the number of step wedge steps between the vertical line from Dmin and the vertical line from Dmax If your step wedge has thirty or thirty one steps the value is 0 10 if it has twenty or twenty one steps then the value is 0 15 Depending on the paper s grade or filter used to print on multi contrast paper you should have a number that is in the ANSI range for your grade or filter This will be the constant we will be developing the film to achieve There is also a visual approach you can take to establish your paper s ex posure range By ma
23. compensates for the overexposure of the fore ground and the areas through the windows in the background This creates the previsu alized image Photos by Glenn Rand USING MULTIPLE EXPOSURES HAS A NICE APPLICATION IN THE DIGITAL REALM fully blend into the tones of the picture The closer to the lens the card is and the larger the aperture the softer the image on the negative Even if the card is only an inch or two from the lens the line created by the card will destroy the image If the exposure is suitably long then vibration or movement will soften the edge Second with this technique or multiple long exposures you may have problems with intermittency effect or reciprocity failure Both approaches work for digital photography With the camera on a tri pod using multiple exposures has a nice application in the digital realm By using the bracketing option on many DSLR cameras the normal exposure can be set as an underexposure by the amount of exposure equivalent to half the previsualized dodge This means that the on exposure will actually be underexposed and the lower bracket will be two brackets underexposed This allows for layering of the top bracket the proper exposure and the under exposure bracket the dodged exposure A more robust but similar process is used for high dynamic range imaging HDRI See page 124 for more in formation on this process PREEXPOSURE The dynamic range of the film can be expanded by
24. essary In metering I found there was two more stops of dynamic range in the scene than the film would normally handle Note that this exposure development relationship could be used for the rest of the roll of film or throughout the day as long as the light and subject stayed the same Photo by Christopher Broughton Right Garmisch Germany 1996 1 Dark est tone meter reading f 2 2 Brightest tone meter reading f 11 3 Area metered for ex posure as Zone III Photo by Glenn Rand Below This image shows the effect of the N 2 development on the scene s tone Wi ey y jT VELA ie a EAA A Kanti BLE di IN d Ori Pe 1H d Example 2 This scene was photographed after sunset and included an east facing wall To begin I looked at the overall light and chose as the darkest point the dark part of the vine I metered that area with a spot meter and got a read ing of f 2 The highlight reading was f 11 Therefore the highlights and shadows were five stops apart This meant there was less dynamic range in the scene than the film was capable of presenting Therefore the development needed to be expanded to bring the highlights to fill the paper s exposure range Here s how it was done 1 Determine the light Normal light has a seven stop range The metered light in the scene ranged from f 2 to f 11 or six stops THERE WAS LESS DYNAMIC RANGE 2 Calculate the development Normal Light
25. exposure with a pre dictable change in tone Note This concept is covered in detail in the fol lowing chapter You should expect some soft detail on the negative before you achieve white At higher zones the relationship between steps will not THE ZONE SCALE 35 translate directly from exposure to print It can be accurately placed at three stops of overexposure from the meter reading Zone IX Near White This zone can be seen as different from white but only through a side by side comparison Like Zone I at the dark end of the gradient Zone IX correlates to a point that can be defined densitomet rically Zone IX is at the place where the shoulder rounds off If a print is measured at Zone IX its density will meet an ANSI standard for Dmin B F 0 04 This should not be confused with the measurement of film FB F 0 04 that is Dmin Because Zone IX is close to white it provides highlight accents within the image Along with white it will create pattern in Zone VIII Zone X White White is any value that reflects more light than the Dmin of the paper Though the paper will gain some chemical fog during develop ment this is not perceptible In most situations the whiteness of the paper base determines the way Zone X will appear Depending on the base materi als coatings and processing the reflectance of the paper base will change 36 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY CREATING A ZONE SCA
26. filters or higher grades of paper This will flatten the picture and can enlarge black holes When we look at a scene this is the zone that is normally seen as the darkest area Zone II Patterned Darkness Zone II is the darkest tone that supports any picture information beyond tone In the print it will be about 5 percent reflective which is just above the upper limit of what we normally call black Soft detail and pattern can be perceived within these dark areas because Zone II is not the darkest possible tone However it cannot display as much tex ture or pattern as Zone III THE ZONE SCALE 31 Because Zone II is located directly on the straight line portion of the film s characteristic curve it is the first zone that can be consistently placed This is done by taking a reflected light meter reading and underexposing by three stops The concept of placing zones will be covered in detail in the next chapter DETAIL ZONES ZONES III IV V VI AND VII Zone III Shadow Detail In many ways Zone III is the most important zone It is the darkest area of the scene where we can see sharp detail with full texture Zone III sets the information flow in the image in much the same way as the underlying melody sets the structure of a song If you choose to have the majority of the information in Zone III then the photograph can easily take on a mysterious feel In low key images Zone III will carry the majority of the information since t
27. in white highlights or significant degradation of the image This find ing is accurate for the camera being used in manual or any automatic mode The white target measurement establishes the number of stops you should open up by when using highlight metering If the meter reading for the white target was 21 3 stops beyond the exposure for the EI and the overexposure ac ceptability is one stop then the correct exposure for highlight metering is obtained by measuring the brightest point in the image and opening up 314 114 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY The two examples show a normal exposure top and a two stop overexposure test bot tom Our task is to find the highest level of exposure in which detail is maintained in the white textured area of the image Photos by Tim Meyer Photo by Glenn Rand A GOOD BET The Sekonic L 758DR light meter creates exposure profiles including EI overexpo sure information and the dynamic range for the camera providing a convenient ref erence that contains all of the information you need to use the Zone System when working digitally stops The number of stops varied from the meter reading that established the EI is the highlight exposure adjustment This will place the highlight meas ured below the clipping threshold DIGITAL ZONE EXPOSURE Though we discussed the ways the Zone System can be used for both film and digital capture some of the consi
28. is detail in the clouds as well as in the shadow details Photo by Glenn Rand anchored moving the slider will adjust only the highlights Move the slider until the data is close to but not at the extreme right edge of the histogram Adjust the Contrast slider to increase or decrease the tonal difference between the darkest and lightest parts of the image When the slider is moved toward the right produces a positive number a contrastier image results When the slider is moved toward the left produces a neg ative number the tonal range is wider and contrast is diminished This wider tonal range allows for a more optimal output Moving the Saturation slider to the right can boost the intensity of the colors in the scene but it should be used sparingly as it can also pro duce an unrealistic portrayal of the scene By moving the slider to the extreme left edge you can create a grayscale image from a color original Though this is a simple approach one of the many other available color conversion methods will produce a better result Once the preview image appears as desired rename and save the file The raw file converter will then process the image and save it as an inter y xi 2 a ii ann ai LE eee SE M BEM R n ee ai i 1 polated file Renaming the file ensures that your original unedited raw image is preserved and unaffected by any image editing Safeguardin
29. min 12 min N 1 2 8 min 30 min N 2 15 min 1 hour N 2 In long exposure time situations there will need to be added exposure in order to achieve proper exposure in the shadow In long exposures the film s ability to capture and hold the latent image the image not visible on the film until development is less effective and decreases as exposure time increases However the highlights are not affected in the same way This creates dif ferent exposure requirements for the various portions of SBR Once again we use the concept of exposing for the shadows and develop ing for the highlights To create a negative that will print well we will increase the exposure for the shadows and thereby boost the highlights This will raise the contrast of the scene To develop the negative to fit our paper s exposure range we will use N development Reciprocity failure occurs differently from one film type to the next For conventional grain films Ilford HP5 and Kodak TriX the rule of thumb is to double the exposure one stop for exposure times between one and nine seconds two stops for exposures of ten to ninety nine seconds and three stops for exposures over one hundred seconds This is a generally accepted practice and the actual changes are not in steps but are gradual This is evi dent in the chart above You will also note the development compensation re quired to shift the highlights to a useable level for the paper s exposure ra
30. neither image matches the previsualized image the right image contains data that can be adjusted in post capture to match the previsualized photo Photo by Glenn Rand 118 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY light exposure metering is used to set the exposure Even if the dynamic range is within the capture range of the sensor it is the highlights that are critical 6 Out of dynamic range exposure If the dynamic range is beyond the capacity of the sensor normally beyond twelve stops you need choose what you will sacrifice the highlight or shadow detail This situation normally occurs when shooting on a bright sunlit day on sand or snow MODE TO MAXIMIZE THE POTENTIAL with deep shadows If the shadow detail is more important you will OF THIS APPROACH need to open up additional stops to include the dark tone detail This CAPTURE YOUR IMAGES IN THE RAW operation will block up the highlights If the highlights are more impor tant use the highlight exposure adjustment It is important that you capture your images in the raw mode to maximize the potential of this approach Other file formats particularly JPEG compress the images and this can result in a loss of image data when the images are opened Furthermore raw images are stored with the captured dynamic range intact Though the raw file converter in your image editing software will spread the captured dynamic range across all 16 bits as seen on the com
31. oie owe a tardawad oo owed a ee eee 101 Bleaching iia alee ioe aa es hae ede es 102 Intensifying Toning Negatives 104 10 THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY 105 Issues for Digital Photography in a Zone System Approach 107 Defining the Parts of a Digital Zone System 112 Testing nic beens aaah chee es a Seas 112 Digital Zone Exposure 004 115 Using the Digital System 0 118 Post Capture Processing 119 Output recto Yea EE A E a coeds 122 High Dynamic Range Imaging 124 CONCLUSION A Personal Approach to the Visual Language 125 Dr Glenn Rand has taught and administered in public education community colleges and universities since 1996 Since 2001 he has taught in the graduate program at Brooks Institute in Santa Barbara CA where he serves as acting graduate program chairman In conjunction with these academic roles and consulting he has devel oped and reorganized several curricula for fine art pho tography commercial photography digital imaging and allied curricula His teaching has included courses in lighting as well as commercial and fine art photography He received his bachelors degree and master of arts from Purdue University He earned a doctorate from the University of Cincinnati centering on the psychology of educational spaces and did post doctoral research as a visiting scholar at the Univers
32. other aspects of the Zone System that can be used with digital capture as well These parts in clude the relationship between reflective intensities the zones exposure reg ulators and the importance of output considerations The zones represent one stop exposure separations across the tonal range from pure white to pure black There is no difference between film and dig ital and we can consider the zones to have this relationship across their func tional dynamic ranges For most situations the dynamic range of a digital sensor is adequate to cover the range of light in the scene Therefore zone placement in exposure is possible With digital as with film capture opening up one stop will lighten the metered area one zone and closing down one stop will darken the metered area one zone This applies to color digital im ages as well As with film middle zones provide image information dark zones provide richness and saturation of color and the highlight zones add sparkle to the image TESTING With digital capture we need to concern ourselves with highlight exposure instead of using dark tone metering as the basis of exposure When working 112 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY l Photo by Glenn Rand PREVISUALIZATION IS KEY TOA SUCCESSFUL DIGITAL IMAGE JUST AS IT IS WHEN USING FILM T a D v i i 7 Tr Test setup Photo by Tim Meyer with film we ran a film speed test to opti
33. over your lens take a TTL meter reading then stop down the lens as needed If you are using sheet film you can use artificial lighting when returning to your studio or darkroom RECIPROCITY FAILURE COMPENSATION Reciprocity is a key component of the Zone System As we saw earlier reci procity functions in the straight line portion of the film s characteristic curve When the exposure of the film does not reach the level of the straight line IN CAMERA CONTRAST CORRECTION 87 i EFNI hile ligt i D aia ST eG then a consistent change in the amount of exposure does not achieve a con yi A S sistent change in density This is referred to as reciprocity failure With reciprocity failure we cannot expect that correct exposure will occur This happens in very long and exceptionally short exposures Most com monly reciprocity failure happens with very long exposure times Since short exposure reciprocity failure happens at extremely short times such as high speed strobe that situation will not be covered in this book 88 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Robert Smith RECIPROCITY FAILURE OCCURS DIFFERENTLY FROM ONE FILM TYPE TO THE NEXT KODAK TMAX 100 Metered Time Exposure Time Development Comp 1 sec 1 sec N 2 sec 2 sec N 4 sec 5 sec N 8 sec 12 sec N T5 SEG 25 sec N 2 30 sec 55 sec N 2 1 min 2 min N 1 2 min 5 min N 1 4
34. placement This concept de pends on some other important concepts though so before we turn our at tention to zone placement we ll need to understand a few other fundamental concepts THE LAW OF RECIPROCITY The law of reciprocity is a key consideration when using the Zone System In a nutshell the law states that as one part of the system is increased another part of the system is decreased to keep the system in balance At the center of the photographic system is a 2 1 ratio For instance the amount of light striking the film is either doubled or halved when a one stop exposure change is made Changing the aperture setting from f 8 to 5 6 doubles the expo sure and stopping down from f 8 to f 11 halves the exposure A shutter speed of one second gives two times the exposure as 1 2 second The film speeds are also based on a 2 1 ratio An ISO rating of 200 is twice as fast as ISO 100 The law of reciprocity allows us to produce a series of equivalent expo sures by opening up or stopping down and changing the shutter speed set ting accordingly For example an exposure setting of 8 at 1125 second is equivalent to a setting of 11 at Yo The idea of equivalent exposures only works because of reciprocity Many photographers think of reciprocity as the change in exposure effec tiveness because of long exposure That is actually reciprocity failure We will deal with reciprocity failure later in the book ZONE PLACEMENT 39 THE
35. range but make areas of the scene increase or decrease in brightness without necessarily changing the dy namic range of other parts of the photograph Most common of the contrast filters are red yellow orange and green Red is useful for darkening green and blue comparatively It increases con trast in landscapes by darkening foliage while creating dramatic sky effects by greatly increasing tonal separation of clouds or subjects against blue sky It 80 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Three separate color contrast filters were used in converting from the raw file to black amp white The sky was approached as though it was captured using a deep yellow filter darkening the blue the yellowish hill was adjusted as though a light blue filter was used adding tone to the shadow areas of the grass and the stop sign was approached as though a green filter was used darkening the red portions while leaving the white in the sign brighter Photo by Glenn Rand THERE ARE ALSO SOME FILTERS THAT ARE PARTIALLY COLORED AND PARTIALLY CLEAR The freshly whitewashed wall had two sets of handprints applied These were made by dipping the hands in a light ochre yellow brown mud and pressing against the wall While the larger handprints were very visible the smaller and lower handprints were very faint and yellow To increase contrast between the yellowish color of the mud and the white wall a blue filter was
36. serving the scene Also now that you are armed with the knowledge you need to make negatives that will fit your paper you will make better prints It may not be possible to make perfect negatives but the closer your nega tives are to fitting the paper the fewer problems you will encounter when you print your photographs ME epee ako In the diagram on the left you can see the fit that the Zone System pro vides When we select the tones in the scene and assign them to zones that represent the way we want to see them in the print we choose a devel opment time that will provide the same range in the film the density difference between Dmin and Dmax as the exposure range of the paper We are using our formula and balanc ing We convert the formula for the system and come up with a new for mula that equals zero Because the paper is a constant we find that the light and the development must be the inverse of each other Our equa tion changes from Print Light x Development to simplified These graphs show the relationship between the scenic light flare the film and the paper Light Development 0 MAKING PHOTOGRAPHS 65 Facing page Photo by Glenn Rand WE START TO VISUALIZE HOW THE LIGHT WILL BE REPRESENTED AS TONES IN THE FINAL PRINT There are two distinct methods for using the Zone System an overall ap proach and a tonal specific approach Within the overall ap
37. shot If your camera allows adjusting the aperture setting in 1 2 stops you will y J g p 8 ps y repeat steps 5 and 6 until you expose seven frames nine including the two taken with the lens cap on If your camera allows for 1 3 stop ad justments repeat steps 5 and 6 until you expose ten frames twelve in cluding the two taken with the lens cap on Reset your camera s ISO setting to match the film s printed ISO rating and finish the roll with normal exposures This is important If you fail to finish the roll the developer will have fewer frames to work on and overdevelopment may occur on the tested frames We have made a roll of film with a series of expo sures at different exposure indices We are estab lishing the exposure index that is accurate for the film Readers will a basic understanding of the Zone System will note that stopping down four stops in step 5 and making the incremental changes we produced all Zone I exposures This zone con cept will be covered in chapter 3 Develop the film using your standard develop ment method and time The resulting strip of film will have two blank frames at the beginning then a series of frames starting relatively thin and fading to no density Once the film has dried read the negatives with a densitometer The following instructions will as sume you re using ISO 100 film If you re using some other ISO your results will be similar but the
38. that you can focus the meter on the tonal area you want to meter A third type of meter a handheld spot meter is a narrow angle light meter used to take ac curate reflected light readings from a small area of the subject Such a meter allows you to stand farther away from subject or tonal area A spot meter is your best choice when using the Zone System Today most meters provide a digital readout This can cause small prob lems in converting from a world of smooth transitions of light analog to a measure of specific numbers digital If you are using a digital meter re member that there may actually be important tonal shifts that fall between the values on your meter s readouts Though this will not affect most pic tures it can have a visible effect in some cases Being aware of the subtlety of the light is where the Zone System comes alive The Target To run the film speed test you will need to photograph an evenly lit target It is best to use one comprised of a white board with a large black rectangle at the center i e the target should be predominately black with a white border This type of target takes into account the effect of sce nic light when testing your film Because the target has a white border re GETTING STARTED 13 flecting toward the camera lens a small amount of flare is created that affects the exposure Since flare is a normal part of all photography including it in the target design provides a more na
39. the dark zones 0 I and II formed the patterns These zones will only be seen when compared to lighter zones Photo by Glenn Rand ZONE II IS THE DARKEST TONE THAT SUPPORTS ANY PICTURE INFORMATION BEYOND TONE Zone I Near Black This tone is visually discernable from Zone 0 but without black to compare it with it might be wrongly assumed to be Zone 0 In the previous chapter s film speed test section you learned about the significance of a densitometer reading of FB F 0 10 Here it is useful to note that this value is equivalent to Zone I As discussed on page 30 the densitometric value of FB F 0 10 establishes the starting point of the straight line portion of the film s curve This is the point where we see the predictable change in density with increased units of exposure On a perceptual basis this means that above this point each one stop increase in exposure will increase the density one zone Thus Zone I be comes the point where the Zone System becomes most predictable This concept of predictability is what the Law of Reciprocity is all about Note the Law of Reciprocity and characteristic curves are discussed in greater de tail in the next chapter Finally since Zone I is close to black it has similar qualities to Zone 0 it too creates pattern texture and detail in dark areas of the image It also cre ates subtleties in an image Beginning photographers often eliminate Zone I by using higher printing
40. the dif fuse light and stop it from reaching the lens surface thereby reducing flare This is as important in diffuse lighting conditions as in direct sunlight While not part of the picture taking process you can produce flare when printing in the darkroom It can be generated from fingerprints old enlarg ing lenses the use of white burning boards or a white wall directly behind the enlarger and will reduce contrast in the final print If we think of the relationship between the parts of the capture to print process we can think of the continuum of light as scenic flare The light in 46 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY EXPOSURE LATITUDE The negative effect of flare is exception ally pronounced in digital images because digital capture is highly intolerant of over exposure Film in contrast is more for giving of overexposure IT TAKES ONLY A LITTLE INCREASE IN DENSITY TO CHANGE THE DARK AREAS OF A PICTURE Photo by Christopher Broughton the scene varies greatly and our eyes through adaptation and other physio logical functions can see a great deal of that light However film and image sensors do not have the same dynamic range and can record only a portion of the total light that might be in the scene Through exposure we can select a contiguous portion of the light in the scene This light might be in the deep shadows or the bright highlights but the recording of the l
41. these qualities on the negative we must maximize the development process to ensure that we can print an image that matches our creative vision Though the Zone System may seem complicated following the steps the method requires will allow you to become consistent in the way you work and lead to better results As you become more and more consistent you become free to say more with your photographs When consistency replaces happy accidents your vision will emerge Though using the Zone System can ensure that the image you produce is technically excellent following the approach alone does not make a picture art After all what does it matter how elegantly you speak if you have noth ing to say So while the main emphasis of this book is the technical approach to making excellent black amp white photographs it will be your vision and interpretation of the world around you and how you communicate this through black amp white photography that determines your success as an artist THE ZONE SYSTEM LOOKS AT THE PHOTOGRAPHIC PROCESS WITH THE FINISHED PRODUCT IN MIND Photo by David Ruderman USING THE ZONE SYSTEM REQUIRES A SCIENTIFIC APPROACH TO CREATING ART CHAPTER ONE GETTING STARTED Using the Zone System requires a scientific approach to creating art To pro duce images that match our creative vision we must fully understand and anticipate the way the existing light affects the scene how to best capture d
42. 25 was entered into the light meter 4 Expose for the shadow detail I took a meter reading at the area I wanted to represent as Zone III in the print 5 Set the exposure I stopped down two stops from the exposure reading obtained in step 4 and made the exposure Processing the film upon return to the darkroom I used D 76 1 1 for 12 2 minutes at 70 F This exposure and processing allowed me to adjust the tonalities of the scene to pro duce a negative with a five stop density range between the previsualized tonal areas of the scene Since there were no very bright areas in the scene the overdevelopment moved the light middle tones up to become highlight detail areas of the print As was shown in the last two examples we can determine the way the print will look based on the way we expose and process our images The system will allow us to move the zones in brightness including the amount of tonal separation however the Zone System does not allow a brighter tone to be made darker than an existing dark tone Also the system works better if there are at least two zones between our previsualized areas Note that compacting two adjacent zones will be exceptionally difficult INCIDENT METERING Though using a reflected light meter is our best bet in most Zone System applications an incident meter can be used for the overall approach see pages 69 72 and in studio situations For an overall approach an incident reading with t
43. CHARACTERISTIC CURVE A characteristic curve is a graphical representation of the way various photo sensitive materials respond to a light source The curve shows the way in which density plotted on the vertical axis is affected by an increase in ex posure plotted on the horizontal axis Note The actual characteristic curves and the zone relationships are not this equally spaced they have been sim plified for ease of discussion The Paper Curve The paper curve has three distinctive parts the toe the shoulder and the straight line The toe is the lower portion of the curve and includes Zones X and Ix Zone X falls below Dmin and Zone IX is located on the curved por tion Zones 0 and I are represented in a similar area at the shoulder of the curve The curved part of the toe and shoulder show the tonal compression of Zones I II VIII and IX in the print Zones II through VIII appear on the straight line portion of the curve In Placing the Zones on pages 41 42 you will learn how reading the curve will allow you to perfect your printing techniques to ensure an excellent print The Film Curve The film curve is comprised of the same parts as the paper curve the toe shoulder and straight line areas However in the film curve the shoulder is not as pro nounced and the slope of the curve is shallow compared to the paper curve The slope of the curve is referred to as the contrast index average gradi
44. D DVD 122 inkjet printers 110 111 124 offset printers 124 online viewing 124 Overdevelopment See Expansion compaction Overexposure 43 64 86 113 114 115 116 117 118 P Paper 36 37 40 41 42 49 53 56 93 97 Pre exposure 85 87 101 2 Presensitizing See Flashing Previsualization 8 12 21 47 53 67 Printers 110 111 124 Printing darkroom 93 100 development 93 97 global controls 93 local controls 97 100 multi contrast 96 R Reciprocity failure 85 87 89 90 Reciprocity Law of 31 62 Resolution 124 S SBR See Subject brightness range Shutter speed calibration 10 Speed point 46 62 Step wedge 54 55 62 Stop bath 95 Studio 9 Subject brightness range 60 61 89 T Target metering 13 14 Tonality 21 22 Tonal relationships 48 49 Toning negatives 104 Tripod 16 82 U Underdevelopment See Expansion Compaction Underexposure 36 85 V Variables 9 10 53 68 Ww White point 114 Z Zone 0 30 Zone I 31 Zone IT 31 Zone III 32 Zone IV 32 Zone V 32 34 Zone VI 34 Zone VII 34 Zone VIII 35 36 Zone IX 36 Zone X 36 37 Zones 30 37 69 76 118 dark 30 32 detail 32 35 highlight 35 37 overall control 69 72 76 118 placement 39 44 tonal control 72 76 Zone ruler See Zone scale Zone scale 29 37 INDEX 127 TAKE CONTROL OF YOUR PHOTOGRAPHY AND LEARN HOW TO ACHIEVE CONSISTENTLY EXCELLENT RESULTS A a photographer th
45. ER DARKENS BLUE SKY AND INCREASES CLOUD SEPARATION AT SOME ANGLES MANY OF THE TECHNIQUES USED IN PRINTING CAN ALSO BE USED DURING EXPOSURE Photo by Glenn Rand formation that comes with your filters for those factor numbers Another way to arrive at the factor is to use a spot meter to read a gray card and then meter the same gray card through the filter DODGING EXPOSURE Most of us became familiar with dodging and burning prints when we began to learn black amp white printing However what many photographers fail to realize is that many of the techniques used in printing can also be used dur ing exposure Dodging exposure for instance can be done in two ways through long exposure or multiple exposure In either situation you will need a tripod and black matboard For long exposure dodging the matboard card is positioned prior to ex posure with the black surface toward the camera so that it will block the area of the scene that is too bright The card should be as close to the lens or lens shade as possible As you start your exposure begin moving the card out of the way Move the card in and out of the frame much like vibrating to re peatedly expose and block the light over an area of the image Ensure that this movement is smooth as your skill in dodging will be evident in the final image Due to the limits of our hand speed and the optics in our camera we will not be as accurate in dodging exposure with fast shu
46. Glenn Rand are held in the collections of thirty public museums in the United States Europe and Japan and are widely exhibited His photographs have also been published in editorial illus trative and advertising functions He has published and lectured extensively about pho tography and digital imaging covering topics ranging from commercial aesthetics to the technical fine points of lighting He is the author of numerous books and con tributes regularly to various periodicals such as Range finder magazine of which he is a contributing editor ABOUT THE CONTRIBUTORS known photographers such as John Sexton through short courses and workshops David works in Sacra mento CA where he exhibits and has his work pub lished While transitioning to digital photography David s photographic experiences are heavily weighted with his black amp white photography ROBERT SMITH Robert Smith BA MS is a long time faculty member at Brooks Institute in Santa Barbara CA who taught full time for more than twenty years and re mains a part time faculty member Before coming to Brooks Smith s career included celebrity portraiture and advertising photography His personal work seeks to cap ture the play of light and design on the natural landscape and in the unexpected abstraction found in abandoned man made objects His photographs are included in pri vate corporate and museum collections and exhibited in many one man and g
47. ISO numbers listed will differ Here s how it s done 1 Use the densitometer to take a reading of the Photo by Christopher Broughton two blank frames at the beginning of the roll the ones created with the lens cap on The resulting number is your film base plus fog FB F reading 2 Read each subsequent frame and record the readings on the appropriate line below The darkest frame should be the first one after FB F lightest to the farthest right If your camera s ISO setting was adjusted in 1 stops in the film speed test use the following chart FB F 25 2 40 80 100 125 160 50 64 200 If your camera s ISO setting was adjusted in 1 2 stops in the film speed test use this chart FB E 25 32 40 50 64 80 100 125 160 200 Your optimal film speed setting with the tested film will be the ISO closest to FB F 10 If FB F 10 lies equally between two frames choose the lower ISO setting 18 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by David Ruderman CHAPTER TWO UNDERSTANDING LIGHT To use the Zone System you must understand how light affects your subject or scene You must also learn how light will be translated into a range of tones from pure black to pure white when the scene is captured in black amp white These tones are called zones The concept will be covered in detail in chapter 3 By cultivating
48. LE To create your own zone scale you can make a series exposures of a textured ma terial then print each exposure and arrange the frames from darkest to light est Here s how it s done Make a target by taking a piece mod erate toned matte textured material e g a towel and affixing it toa board so it stays flat Position the material in sunlight or under a single light source so that its texture is apparent With the camera on a tripod focus on the surface No shadows should fall on the target other than those created by the material itself The frame should be completely filled with the target Take a meter reading from the mate rial assuring that the only reading comes from the target Make a series of eleven exposures from five stops underexposure to five stops overexposure 6 Process the film normally Contact print the negatives being careful to use a low paper grade or filter number to give separation between steps from black to white If you have use of a reflection densitometer control the print time so that your middle tone has a reflectance of approximately 0 74 If you are making this zone ruler without a densitometer then print the middle tone to visually match an 18 percent gray card All negatives should print at the same time or be printed simultaneously Cut the small prints and paste them to a card arranging them from darkest to lightest Facing page and below
49. S 0 I AND II Zone 0 Black Zone 0 is black Think of this as the richest black tone you can achieve on a piece of photo graphic paper True black is the ab sence of reflection but this is very hard to accomplish In terms of the negative there is no usable density The black in a photograph can give richness or can absorb all the energy in the image There are no hard and fast rules about the amount of Zone 0 that will work in a photograph The black establishes the bottom of the print s dynamic range and creates pat tern texture and detail in dark toned areas of the image Too much black can be detrimental to the quality of the photograph because no detail will be visible in such areas and detail is critical to communicate your vision to the viewer Lacking detail large areas of Zone 0 density can be thought of as black holes that absorb energy from the photo as the eye moves across the area DENSITOMETRIC TERMS In the following sections densitometric terms are used to discuss some of the zones These are stated in both how they can be used and in American National Standards Institute ANSI measurements The terms important to the Zone System are Dmin the least use able density on a negative that is defined by ANSI as film base plus fog plus 0 04 FB F 0 04 and Dmax the highest density that will be useable or as an ANSI standard of 0 9 times the maximum density in a negative These two represent the toe the lowest de
50. TERS Filters provide the easiest opportunity to change the overall or local contrast of a photograph during exposure Two main types of filters absorption and interference filters are used to increase or decrease the contrast that will be created during exposure This can change contrast relationships between varying subjects within a single image Note that another group of filters special effects filters do not affect image contrast First are absorption filters These reduce the amount of light that is trans mitted to the film by absorbing part of the light reflecting from the scene The simplest type to understand are the neutral density filters which are very useful for digital capture These reduce all the light from the scene by the same factor regardless of the color of the light Filters are described in terms of density Using a 0 30 filter will reduce ex posure by one stop These filters allow for the use of larger f stops or slower shutter speeds These filters will affect contrast if they make the exposure fall outside the reciprocity for the film Contrast filters are a type of absorption filter commonly used for black amp white photography These are colored and reduce the effect of the light that is complementary to the color of the filter In this way a red filter will shift the contrast in a picture to make reddish objects record lighter in compari IN CAMERA CONTRAST CORRECTION 79 son to greenish ones The red filt
51. TINUITY OF THE PROCESS FROM ITS INCEPTION ZONE SYSTEM FIELD CHART GLENN RAND FILM FILM TYPE DATE LOCATION PREVISUALIZED METER READING DESIRED ZONE DEVELOPMENT TIME MINUTES OR N LIGHT CONDITION EFFECTIVE BASE EXPOSURE F STOP TIME METER AT ZONE IIIT STOPPED DOWN 2 OR CRITICAL ZONE LENS FOCAL LENGTH BELLOWS DRAW FACTOR STOPS FILTER COLOR TYPE RECIPROCITY CALCULATION STOPS FINAL EXPOSURE COMMENTS FINAL DEVELOPMENT TIME BASED ON RECIPROCITY CHAPTER EIGHT IN CAMERA CONTRAST CORRECTION BEYOND THIS IS THE POSITIVE AND NEGATIVE EFFECT CREATED BY FAILURE IN RECIPROCITY Facing page Photo by Glenn Rand As we move beyond the Zone System we find that there are many parts of the black amp white photographic process that will enhance our ability to commu nicate our visual ideas These expand our vision beyond the literal interpre tation of the scenes we choose to photograph There are two concepts we can use on the negative to allow for expanded potentials In the camera we can modify the way light affects the film Beyond this is the positive and negative effect created by failure in reciprocity Because most digital cameras capture in color some methods discussed here may not seem appropriate but many are In some cases these are handled exactly as they are for film and in some cases they are applied using other equipment or software FIL
52. an understanding of light you will be able to IMAGES WITH A GREATER NUMBER OF TONES CAN DEPICT SCENES WITH MORE DETAIL Facing page Photo by David Ruderman Below Photo by Christopher Broughton read your photographic subject and make creative exposure and develop ment decisions that will allow you to create a print that expresses your cre ative interpretation COLOR AND TONALITY Light is an energy source that makes vision possible and allows photographic capture to happen Some light is invisible Some light the kind that concerns us as we make images can be perceived by the human eye This is termed vis ible light All light is comprised of waves which are described in terms of their length Each of the wavelengths that comprise the visible spectrum can be perceived as a particular color This concept governs our visual perception of the world around us Though it is essential to our perception of the world as we experience it with our eyes we must learn how to translate that per ception if we are to visualize a scene in black amp white To previsualize a color scene as a black amp white image you will need to un derstand how various scenes will appear when devoid of color To approxi mate monochromatic vision seeing in black amp white and to aid in dimin ishing the effect of color some photographers use an amber colored filter e g Wratten 80 to view their scenes This renders the scen
53. apture to print process This allows me to expend my mental energy for the purpose of perceiving and interpreting the world I Photo by Glenn Rand encounter and communicate through my photographs CONCLUSION 125 INDEX A Adobe Camera Raw 119 24 Adobe Photoshop 114 119 24 color sampler 114 CS2 119 122 CS3 119 122 curves 122 histogram 122 ANSI 36 54 55 Aperture calibration 10 Average gradient 40 B Background 113 Bleaching 102 3 Blooming 114 Burning 97 99 100 101 c Characteristic curve 40 41 56 64 87 film curve 40 41 42 48 54 56 64 paper curve 40 41 42 48 Chemical fog 36 Chromatic adaptation 24 Clipping 111 114 115 Color 21 22 111 Color fringing 114 Constants 9 10 53 54 Contrast 28 40 46 62 79 92 100 101 103 111 correction 79 92 index 28 40 46 62 Contrast range See Contrast index D Dark slide 57 Density 30 46 50 54 88 Densitometer 30 53 58 64 Development 53 64 93 97 Digital capture 85 105 124 Digital sensor See Image sensor Dmax 41 49 55 56 58 59 94 101 103 Dmin 36 46 48 49 55 56 58 59 86 101 103 Dodging 83 85 97 100 101 Dynamic range 23 24 25 27 36 37 44 47 48 53 62 69 70 71 72 118 E Eighteen percent gray See Zone V Enlarger 46 54 56 57 101 2 Expansion compaction 49 51 56 60 61 62 64 70 75 76 89 93 94 Exposure index 18 30 55 113 114 115 118 Exposures mul
54. area to be lightened Slowly lighten the area with repeated applications of solution If you are using the bleach fix process you will not see the effect of the bleach until after fixing the bleached area ADVANCED PRINTING TECHNIQUES 103 INTENSIFYING TONING NEGATIVES Like bleaching intensifying can be used for local or global control Intensi fiers not only darken the negative in doing this they raise the contrast of the negative They work by molecularly bonding to the silver in the negative and producing more density Most intensifiers increase density proportionally to the amount of silver present in the negative This means that the darker areas of the negative take on more density than thin areas This gives a similar ef fect to overdeveloping without increasing apparent grain Selenium toner can also be used for this purpose If you wish to intensify a small part of the negative this can be done with a fine tipped brush a light table and a selenium toner solution To make the selenium toner solution mix one part Rapid Selenium toner with one part working strength hypo clearing agent The hypo clearing agent is used in stead of water because it penetrates the negative more effectively With the dry negative on a horizontal light table the solution is applied to the areas of the negative that you wish to intensify Be careful because once the selenium reaches the negative it changes the density permanently By using this tec
55. ariations to the left of the green line from Dmin will reproduce as white and light variations to the right of the green line from Dmax will show as black curve is the tone that will reproduce as white This may not be the bright est light in the environment but be cause of the way the film develops and the limits of exposure of the paper it will be reproduced as white Though the film has greater latitude to capture and develop tone than does the paper it is the exposure lim its of the paper that will determine the tones that appear when the image is printed The tonal exposure range of the paper is the controlling factor for the system This is the amount of expo sure the paper will accept from the negative any value variations below Dmin or above Dmax will not be seen in the final print If the negative lets in less light than is needed to expose the paper for Dmin then that will be indistinguishable from other areas of white Also if the negative passes more light than is needed to achieve Dmax it will be black regardless of the detail that might be present in that thin portion of the negative Our goal then is to make negatives that include information from the scene that won t exceed the paper s exposure range At the least technical level this means we must know how the light in the scene compares to normal light If we can determine that the light for our photograph uses more of the flare curve and has a
56. avid Ruderman Ruderman produced an image that uses only the highlight zones VIII IX and X The shadow detail in this image is found in Zones VI and VII Photo by David Ruderman THE ZONES ABOVE ZONE VII WILL BE DIFFICULT TO DEFINE AS SIMPLE CHANGES IN UNITS OF EXPOSURE As we move to higher zones the lack of tonal separation will not allow us to interpret the information within the lighter zones With the sharp detail and full texture available in Zone VII it is used as the high end for average value metering Within the printing process Zone VII is a target for establishing proper print densities This is because as discussed above the density changes in the higher zones are affected by printing from the shoulder portion of the film s curve thus showing larger tonal areas than previous zones The zones above Zone VII will be difficult to define as simple changes in units of exposure HIGHLIGHT ZONES ZONES VIII IX AND X Zone VIII Patterned Highlight Zone VIII is the lightest information zone beyond highlight tone In the print it will be the lower limit of what we normally call white Because there are two zones lighter than Zone VIII we can see pattern and soft detail in this light area Though there is no strong de tail in Zone VIII it is a visually active area of the picture Located at the point at which the shoulder of the paper curve rounds off Zone VIII is the last zone that matches a change in
57. aw a F gt FILM amp DIGITAL W J TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY m Tort F 4 4 xf Y F a t P k eg A ot F i ek A r A EA a n ae n pE Ea i i gt in Pi p l DR GLENN RAND F Amherst Media rri Pi EF Copyright 2008 by Glenn Rand All photographs by the author unless otherwise noted Front cover photograph by Glenn Rand Back cover photograph by Christopher Broughton All rights reserved Published by Amherst Media Inc P O Box 586 Buffalo N Y 14226 Fax 716 874 4508 www AmherstMedia com Publisher Craig Alesse Senior Editor Production Manager Michelle Perkins Assistant Editor Barbara A Lynch Johnt ISBN 13 978 1 58428 227 3 Library of Congress Control Number 2007942654 Printed in Korea 10987654321 No part of this publication may be reproduced stored or transmitted in any form or by any means electronic me chanical photocopied recorded or otherwise without prior written consent from the publisher Notice of Disclaimer The information contained in this book is based on the author s experience and opinions The author and publisher will not be held liable for the use or misuse of the information in this book About the Author 0 ce ee 5 About the Contributors 0 0 0 6 5 INTRODUCTION annaa 7 The Conc pt aia e ok een ee se eh eee ees 8 1 GETTING STARTED 9 Variables and Constants
58. capture Humans can perceive a wider range of tones than can be captured on film or reproduced in the print The human perceptual system has the ability to see a 1 000 000 1 dynamic range This range would include being able to see black print on white paper under starlight at the low end and the sun at the high end While we can see the sun the light is so intense that it will lt l y damage the retina of our eyes This means that we can see light throughout a twenty stop range Film on the other hand can only capture a 1 000 1 dy namic range without manipulated development This is equivalent to about a ten stop range Because we can see a wider range of tones than we can cap ture we need to learn how to modify the way we look at a light range as we attempt to photograph a scene This is one of the main concepts of the Zone System Human vision has another advantage over photographic capture chro matic adaptation This means we can look at the side of a white building in shade and process it as white Unfortunately film cannot adapt It holds a constant dynamic range This means that our film will record the shadow side of the building not as white but as gray Fortunately through exposure con trol we can manipulate the limits of the film However it is important to re alize that as we make exposure adjustments we are not impacting the dynamic range of changing the film s exposure latitude Rather you a
59. curve crosses the lines labeled N 3 through N 2 In this way we see that a six minute developing time is N 2 development 6 67 minutes is N 1 7 5 minutes is N 9 minutes is N 1 and 11 minutes is N 2 Extending the line beyond our last point we can approximate that 13 5 min utes will equal N 3 The numbers and times are examples only The last bit of information we need to generate from the testing is the ef fective ISO The logic is simple in adapting the film for different SBRs we need to overdevelop or underdevelop We are manipulating development to control the highlight detail in the negative Exposure controls the shadow details Remember we want to expose for the shadows and develop for the highlights Therefore we need to be sure that the shadow will receive the correct amount of exposure based on development With underdevelopment DEVELOPMENT 61 there will be less shadow detail than with normal de velopment and the opposite is true with overdevel ey A ET CN FF py Fi opment For this reason we need to establish a Wek by i are os a l ee ee a method for adjusting the exposure and using dif f N ferent ISO settings in the metering system depend Mel i a E AS G E T E ing on the SBR is an excellent approach Calculating effective ISOs for various develop 1O W 180 412 l 118 ments can be done with the same testing materials and on the same set of characteristic curves already The graph shows th
60. density more toward the shoulder When the development changes beyond the increase or decrease in den sity compared to exposure there is also a change in the amount of useable light from the scene Changes in development make the film function better if there is a non normal light situation To see this in the interrelated graphs we start at the paper curve and fol low down vertically from both Dmin and Dmax These are the limits for the amount of light from the film that will fit within the range of the paper If we then change the angle slope of the film curve we can see that less or more of the scenic flare curve is useable as we move horizontally from the inter section points of the vertical lines from the paper and the new film curve rae HT tal dil HEL ELS gE oon Set oP oe epe S ooe 50 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY This diagram shows how the increase in development affects the characteristic curve The red line indicates the normal development and the shaded area under the curve represents the densities created Since development is proportional the more normal density the larger the amount of increased development density The violet color shows the effect of the overdevelopment density increases and the green line shows the characteristic curve coming from this overdevelopment The black white scale at the bottom shows the p
61. derations differ from one approach to the other These are the exposure point and image processing With film we ex pose for shadow detail and thus use dark tone metering to set our exposure Because of digital s comparative intolerance to overexposure we must concern ourselves with highlight based exposure Another difference is that with dig ital development times do not come into play Of these considerations exposing for the highlights has the most profound effect on our thinking and working Image editing software allows us to ma THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY 115 nipulate captured data in the image file and lighten or darken specific parts of the image But it must be noted that if there is overexposure there is no difference between white and any light source that is brighter than white Darkening an overexposed area does not add detail it only grays the tone The approach to working within the environment is comparable whether digital capture or film is used We can certainly use zone placement to estab lish the relationship of any critical zone within the image As discussed pre viously the change of one f stop is equivalent to change of one zone In a digital Zone System while working with selected zones we must consider the effect on the highlight areas of the image If moving a specific tone will force DARKENING AN OVEREXPOSED AREA DOES NOT ADD DETAIL IT ONLY GRAYS THE TONE Photo by Glenn Rand
62. e Zone System offers you a way to cap ture your impression of the world and tell someone else what you saw in the most beautiful visual language the language of black amp white photography Based on the techniques of leg endary photographer Ansel Adams and presented by Dr Glenn Rand of the Brooks Institute this book offers a systematic ap proach that integrates a knowledge of light exposure develop Amherst Media PUBLISHER OF PHOTOGRAPHY BOOKS PO Box 586 Buffalo NY 14226 www AmherstMedia com ISBN 13 978 1 58428 227 93495 34 95 USA 38 95 Canada 1861 9 781584 282273 ment and printmaking By implementing these step by step in structions for each phase in a film or digital workflow you can be come consistent in the way you work and achieve overall better results in your images FEATURES Tips for getting started quickly with the Zone System Identifying the many variables in your workflow and learning how to control them or compensate for them Understanding the zones and how to place them in your images Tips for accurate previsualization Metering techniques for more precise exposures Development techniques for exacting contrast control Printing to bring out the most in each image Implementing the Zone System principles in a digital workflow Images by Glenn Rand Christopher Broughton David Ruderman and Robert Smith
63. e in a sepia tone Squinting is often thought to be a way to reduce color but it only pro duces a change in intensity not a change in color or tonal range In a black amp white image the range of light values present in the scene are depicted as tones Images with a greater number of tones can depict scenes with more detail Imagine an image comprised of only pure black and pure white tones Now imagine an image comprised of a wide range of tones from pure black to dark gray tones to medium dark tones moving all of re a H the way to light gray and pure white When an image incorporates a wide range of tones we can perceive the soft shadow of a dark tree cast on freshly fallen snow We can perceive that the skin tones of a particular subject are lighter than her hair color but darker than her sweater We can also see the pattern and texture of the subject s clothing depicted by varying tones high lights and shadows 22 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Christopher Broughton Photo by Christopher Broughton SEEING THE SCENE HUMAN VISION VS PHOTOGRAPHY Learning to anticipate the way a color subject or scene will appear when ren dered in black amp white is critical to producing a quality image However be fore we can predict the way the scene will be depicted we must investigate the differences between human perception and the capabilities of photo graphic
64. e photographer shifts the detail consideration to highlight separation as opposed to concern for shadow detail Zone V Middle Gray Zone V is often referred to as middle gray It is in the center of the tonal range and is within the reciprocity range Zone I Zone VIII Zone V reflects about 18 percent of the light falling on it Be cause meters are calibrated to this value we can make both technical and aes thetic judgments in relation to positioning against Zone V Note The concepts of reciprocity range and zone placement will be covered in the fol lowing chapter Reread this section once you ve worked through chapter 4 if these concepts are not yet clear to you 32 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Facing page Because it is centered in the middle Zones III VII the image shows smooth tonal changes and soft curved surfaces Both highlights and shadows accent against the broad middle tones Photo by Robert Smith FOR SOME PHOTOGRAPHERS THIS ZONE IS A CHOICE FOR DARK TONE METERING While many people interpret Zone V as darker than middle gray it is both in the center of the system and perceptually the midpoint of the grayscale When seen in comparison to the lower zones its centrality becomes clear At the center of the zones Zone V acts a visual pivotal point for the system Zone VI Light Middle Gray Zone V1 is full of detail The tonal change from middle tones to highlights begins at
65. e range of tones the film can record and reproduce within the exposure and processing system While we may like the light on a sunny day this light may be beyond the normal expectations of the film Depending on the humidity of the atmosphere the light will exceed the dy namic range of the film by as many as three stops In this case with normal development we could not reproduce either the highlight or shadows or parts of both For film normal light is flatter slightly diffuse light that will closely match the film s ability to render the scene giving you a negative that will print well If the light is not normal for the dynamic range development can be manipulated to allow the neg ative to print acceptably TONAL RELATIONSHIPS To see how we can make the film conform to the light without exten sive use of calculations let us exam ine the interrelationship of flare the light in the scene the film curve and the print curve As mentioned above not all light makes its way through the process and is represented in the print Look ing at the diagram we see that some az2290205012 ME eerie koe light represented in the flare curve is below the threshold of exposure for the film it will be located on the toe of the curve with a value less than Dmin This light will have no expo sure value in the negative and will not be seen in the final print At the other end of the useable port
66. e relationship between the exposure index adjusted ISO produced While the method of calculating effective and the dynamic range of the light The vertical scale is in relation to N which film speed i dependent on which measure f slope is normal light having He Stes between Zone III and Zone VII On the hori zontal axis are the proportional adjusted ISOs compared to the published ISO you use the slope of the characteristic curve of the film is key in determining an effective ISO These slope ratings may be re ferred to as contrast index gamma or average gradient Rather than deal with the densitometry for all calculations of slope we will use contrast index CI for our discussion The process requires that we find the curve in the set that has the same slope as the standard CI set by the film s manufacturer You can find the slope of the straight line portion of each curve To do this we will first want to es tablish the speed points on all the curves Since reciprocity kicks in at this point you should start your slope measurement at this point To find all of the speed points find the point on the steepest and shallowest curves The speed point s value is equal to FB F 0 10 By finding the speed points at both ends of the curve you can draw a straight line between these points This line will cross the other curves at their speed points If none of the curves have the same slope as the manufacturer s CI then interpolate the value betwe
67. edge the steps on the graph will be in 1 4 stops Once again we are in terested in the N values and not necessarily our actual points from the char acteristic curves In the graph of ISOs compared to the N values for light if Photo by Glenn Rand the published ISO is 100 then N is slightly left of the published ISO In this case we would use ISO 80 err toward slight over exposure The N I level is crossed about 1 4 of the way from the 4 mark making it function as ISO 80 The N 2 is about halfway to the 1 mark and should use ISO 50 On the other side of N N 1 is not quite to the 44 mark and this indicates that we would use ISO 125 N 2 is at the 1 mark indicating the use of ISO 200 with the extension of the curve for N 3 at 1 indicating ISO 250 In this way we can compensate exposure raising the ISO decreases exposure and lowering the ISO in creases exposure EXACTNESS OF DEVELOPMENT We have now found the three densitometric values that make the Zone System work These are the ex posure range of the paper the amount of light from the scene that will fit the paper based on the film s development time and the exposure compensation needed to make the light properly record the shadow detail To ensure proper results there must be consistency in the developing process Below are two charts that show the tested times for Kodak k S at Tmax 100 and Ilford Delta 100 The third chart Photo by Glenn Rand
68. eed to be concerned with how light is related to the film s sensitivity exposure and processing FLARE Camera System Flare Camera system flare is an unavoidable but somewhat controllable part of photographic capture As light enters the camera the lens not only focuses light from the scene but also captures light from areas not VISUALIZING THE SYSTEM 45 included in our viewfinder This might be the sun shining on the lens from just outside the captured image an overcast sky or other environmental el ements with high luminance or reflectance Some of the light that enters the lens reflects off of the lens elements fil ters or interior surfaces of the camera and finally exposes the film When this light comes from a strong point source polygons of light in the shape of the iris opening appear in the print This can even occur when the sun is not di rectly in the image if its light strikes the lens Scenic Flare Glare scenic brightness overcast conditions and bright skies can create a less noticeable type of flare When the light is diffuse or broad flare creates a broad pattern of light that spreads over a larger part of the neg ative or image sensor Since it is diffuse we do not recognize it in our nega tives or digital files It is not as blatant as those polygons of light however it is there With film the effect of this added light to the negative is not just additional density that we will need to print throug
69. en existing slopes Whether you find a curve s Pipi A elu en tesisu bee slope that matches the manufacturer s CI or interpolate one the point on FIND THE POINT ON THE STEEPEST the line through the speed points locates the published ISO This becomes AND SHALLOWEST CURVES the development time that will result in the film functioning at its published speed Once the development time is established for the published ISO the ISOs for the other development times can be determined by measuring horizon tally to where the other curves cross the speed line If the intersection of a curve and the speed line is one stop toward the toe of the curves the ISO for that curve would be twice that of the published ISO and if it was one stop toward the shoulder then it will be half the published ISO A stop measure ment will be two steps on a twenty two step wedge and three steps on a thirty three step wedge To make a usable tool you can create a graph simi lar to the one used to establish the N developments On this graph the horizontal axis will be the ISOs with the published ISO in the center of the graph If your step wedge was made up of 0 15 steps then the steps on the graph will be in 1 2 units In this case the first step to the right would be 1 2 stop more than the published ISO and two steps would 62 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY be double the ISO To the left the ISO diminishes by 1 2 stops With a 0 10 step w
70. ents your files will be usable as produced so long as it is at a web resolution if required However most professional photographers will need to produce prints and this presents us with a new challenge There is an unfavorable discrepancy between the capture capabilities of a digital image sensor and the printer used to output your image For instance your sensor may be able to capture an eleven stop exposure range but inkjet printers will only be able to reproduce about 7 5 stops and offset printers can only reproduce 3 8 stops of capacity This discrepancy means that some of the detail you endeavored to capture and print in your image will be clipped Fortunately this can be remedied by using Photoshop s Curves feature To do this move the curve down 5 percent from the top and up 5 percent from the bottom HIGH DYNAMIC RANGE IMAGING When the light is beyond a twelve stop range high dynamic range imaging HDRI can be used Newer image editing programs support this process layering a series of exposures made with the camera on a tripod This dis cussion is beyond the scope of this book but informative discussions can be found in books that cater to using image editing software or by entering the relevant terms in your Internet browser s search field 124 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Glenn Rand CONCLUSION A PERSONAL APPROACH TO THE VISUAL LANGUAGE Sharing the visual world in
71. er absorbs more of the green spectrum but has a lesser impact on the red portions of the spectrum The filter reduces all the light entering the lens but has a greater effect on colors that are not in its makeup Because digital cameras capture color hardware 1 e traditional con trast filters become color changing devices Therefore we use software to ac complish contrast filtering as we change the image from color to grayscale black amp white This can be accomplished as an adjustment or adjustment layer The major advantage of working with black amp white images through digital capture and image manipulation software is that contrast filtering can be added to specific areas of the image without applying the filter to the en tire image Color theory shows us that all colors in light are made up of three pri maries red green and blue Mixing all three primaries at full strength cre ates white light If we mix in any other combination we will get other colors The filter works because it is absorbing color that is not in its makeup A red filter is in a primary color and will reduce the portion of the other primaries blue and green Since yellow is made up of red and green light a yellow fil ter will have less effect on reddish or greenish colors while reducing the ef fect of blue light on the film In this way we can reorder the contrast of a scene by using contrast filters The filters do not change the overall dynamic
72. essed when thinking about how an image will be output is that noise is required Noise shows as random specks of value changes within a tonal area Unless the noise is exceptionally contrasty it will be unnoticeable or not objectionable Digital printers need some noise to keep from posterizing prints producing flat blocky tones While a small amount of noise is required in all areas it is most noticeable in very dark areas To prevent highlight blocking and allow for the required noise it is bet ter to use a range of 12 242 than the full range 0 255 of tones available for the image If the minimum value is 12 there will be enough dark tones to permit noise Using 242 as a maximum you guard against blocking up the highlight details This smaller range provides about 7 5 stops of output range which matches the potentials of photo inkjet printers There are two major differences between using film and digital capture that we need to consider First film has a much greater dynamic range than digital capture Black amp white film that has been discussed previously in this lt 110 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY NOISE SHOWS AS RANDOM SPECKS OF VALUE CHANGES WITHINA TONAL AREA Photo by Christopher Broughton Photo by David Ruderman FILM HAS A MUCH GREATER DYNAMIC RANGE THAN DIGITAL CAPTURE at iil a i book can be controlled to produce a dynamic range up to seventeen stop
73. etail and how to refine the development process so that the final print sings When photographers master the steps outlined in the Zone System they can easily predict previsualize the outcome of their prints With the technical success of the image assured we have more mental energy that can be put to ward seeing and composing our photographs VARIABLES AND CONSTANTS Over five thousand variables or more specifically combinations of factors are at play when creating images not including the effects of filtration and advanced printing techniques The light in the scene the exposure the film type and ISO the shutter speeds and aperture the variables at play in devel oping the film and the options we are faced with in printing our images all affect the outcome of our images With so much variability the odds that we will not achieve our goal in con veying our artistic vision are high For this reason one of the most important tasks we must undertake when beginning to use the Zone System is to con trol and eliminate some of the variables and their overall effect on our work This process of standardization is the key to achieving good results Without it you cannot predict the outcome of your efforts Of the many variables the only factor that lies outside our control unless we re working in the studio is the light For this reason it is considered an independent variable meaning we can t control how it changes The other
74. ethod the light s dynamic range must not be too long or too short The method will only work in scenes where there is more than an 8 1 and less than a 32 1 tonal difference That provides a window to use this method if there are between three and five stops difference in the metered values of Zone III and Zone VII To determine this variation simply count the stops between the meter readings of the chosen Zone III and Zone VII There are three stops of exposure difference with 8 1 and six stops difference with 32 1 tonal variation We know that Zone II and Zone VII are four stops apart If the scene we will be photographing has a four stop difference between Zone II and Zone VII then the light fits our expectation for a normal scene In this case we would expose for Zone V that is two stops above Zone III and two stops below Zone VII This is the same logic that we use if there are three to five stops difference between what we previsualize as shadow and highlight detail Within this range averaging the exposure values from Zone III and Zone VII will produce a negative meeting our need for detail without being biased by brightness or darkness in the scene 44 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Glenn Rand Photo by Christopher Broughton CHAPTER FIVE VISUALIZING THE SYSTEM As mentioned in chapter 2 light makes photography and vision possible Be yond understanding how light affects the scene we n
75. g the original raw file ensures that you can work with and reinterpret the image at a future date The following paragraphs explain how Photoshop CS3 can be used to process your image Though the interface and names of some of the controls differ from those used in CS2 processing we will follow the same basic steps to process our images CS3 allows for more advanced Curves control in fact all of the functions discussed previously with the exception of saturation can be controlled by manipulating the curve When the Curves feature is activated the curves ad justment appears superimposed over the histogram of the image To edit the curve click on edit points to modify curve icon at the top left of the dia log box then click and drag the curve itself to adjust the highlight midtone and shadow areas of the image as well as the contrast With the default settings in place and working on an image in the RGB mode pulling the center of the curve down darkens the image pulling it up lightens the image If the top right end of the curve is pushed up and the bot tom left end is pushed down creating an S curve the shadow details will darken and the highlight details will compress and become brighter This will produce a more contrasty image As needed you can remove the anchor points by clicking on them and dragging them off of the curve At the shadow and highlight ends of the curve the endpoints can also be adjusted to change the
76. g the devel opment process will change the angle of the characteristic curve In this case the change indicates that the reduced strength of development of the paper will expand the exposure range of the paper One of the easiest ways to ac complish this weakening of the development is through a water bath process In the water bath processing of paper you allow the paper to develop in still water between developer refreshing This development process is capable of reducing the contrast more than a full grade or filter An increase in exposure may be required to maintain Dmax Since times will vary depending on the variables pertaining to the water and developer it is strongly recommended that you test your paper before 94 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Christopher Broughton using this technique on your fine prints However the following steps will serve as a general guide Expose the paper normally 2 Start the development process by immersing the paper in the developer with adequate agitation After thirty seconds remove the print from the developer and place it in a tray of water Allow the paper to sit in the water without agitation for thirty seconds Place the paper back in the developer for five seconds with vigorous agitation Remove the paper from the developer and place it in the still water for fifty five seconds Repeat steps 5 and 6 two more times Finis
77. h nique you will accomplish a similar effect to dodging with a magenta filter 104 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Christopher Broughton THE DARKER AREAS OF THE NEGATIVE TAKE ON MORE DENSITY THAN THIN AREAS Photo by Glenn Rand CHAPTER TEN THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY Digital photography is very seductive It allows the photographer to do things that were not possible before In digital photography just because you can expose and erase many times does not mean that you should Nor does it mean that you can ignore correct exposure for a post capture fix How can the Zone System benefit digital photographers Perhaps most important is the thinking process we must employ in using the system We must consider the output of the process as or before we make the exposure calculations and before we press the shutter release The Zone System is valu able in digital photography because it can lead us to a system approach re sulting in better communicated portrayal of the scene At the heart of the Zone System is previsualization As discussed earlier in the book previsualization is based on your assumptions of how the scene will look in the final print In digital photography there are no rules that say that 106 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Christopher Broughton Photo by Christopher Broughton you must jettison this type of thin
78. h it also alters the contrast range of the negative Because we are adding light to areas of the negative that would be unexposed or lightly exposed we raise the Dmin or the speed point of the film It takes only a little increase in density to change the dark areas of a pic ture When we looked at the density of the negative we found that we were adding only 0 10 to black to achieve Zone I Moving up the straight line portion of the curve we needed additional density to move each successive zone Therefore adding an overall fogging created by flare to the film will have a greater effect in the areas with the least density These are the dark areas of the picture Adding density to the shadow detail and toe areas of the negative and dig ital capture flattens the contrast It also affects the highlight areas of the neg ative filling in detail or eliminating detail in the highlights This makes it difficult to obtain a discernable difference between Zones VIII and IX This often compounds the problem you have in making your photographs in over cast or diffuse light situations Because this light is diffuse to start with it will give you a flatter image Good technique processing controls and use of multicoated lenses and fil ters can reduce some ambient light flare but nothing can totally remove the effect Your best defense in reducing the flare is to use a lens hood or shade The black interior surfaces of the shade or hood will absorb some of
79. h the print process with stop bath and fixer as normal ADVANCED PRINTING TECHNIQUES 95 a gt a r Bramma mari Beers and Pseudo Beers developers can also be used to control the develop ment speed by the strength of the developer and the makeup of the chemi cal In these cases higher contrast and lower contrast developers are pro 96 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Facing page Multi contrast printing allowed the highlight areas of the print the trees outside the window to gain tones because they reacted to the 0 filter while the dark areas in the burned bricks inside the building gained detail because of the use of the 4 filter Because of the complexity of the image dodging or burning the image would be very difficult Photo by Glenn Rand Below Photo by Glenn Rand portionally mixed to change the developer s effect on the paper With these developer combinations as well as with split bath developing using the two different types of developers separately you can also change the effective ex posure range of the paper MULTI CONTRAST PRINTING Using combination printing of multi contrast paper can give even more con trol of the way various tonal areas of the print are exposed In this situation you print the negative twice without moving the paper or easel The only change in the two successive exposures is in the printing filtration If one of the filters is a low contrast number
80. he light falling on the meter s dome provides a value for Zone V and using the meter within the shadow without light falling on the dome provides a value for Zone III This means that you can read these two areas for normal with two stops in between For studio work photographers often rely on an incident type flash meter Though we control the light in the studio we can still use the Zone System Reading the light ratio which describes the relationship between the main light and fill light can allow us to employ the overall approach to the Zone System We point the dome of the meter at the main light to obtain our first reading then point it at the fill light to establish its value If the desired light ing ratio in the print is 4 1 your readings represent a two stop variation FIELD CHARTS The Zone System requires accuracy and continuity of the process from its inception Note taking will aid you in this process Whether you use a note pad or field charts you will want to follow directions for development N in the darkroom and keep track of your previsualization Use the field chart shown on the facing page to take notes and calculate N development 76 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Above Photo by Robert Smith Facing page Using a field chart like the one shown here will allow you to ensure accuracy and continuity throughout the Zone System process THE ZONE SYSTEM REQUIRES ACCURACY AND CON
81. he areas are not as predictable with a relationship between exposure and tonal change we use the toe area for Zones 0 and I to produce a negative with predictable and thus control lable zones II through VIII on the straight line portion of the curve Since the film s shoulder is not as pronounced as a paper curve the function of our zones extends to include Zone IX Zone X from the scene will be above our Dmax and is beyond the linear relationship we are creating PLACING THE ZONES In the above section we looked at a paper curve and a film curve We noted the various parts of the curve the toe the shoulder and the straight line por tion By reviewing the curves we can learn how manipulating the exposure will impact our final image To get an idea of the way this works let s look at the paper curve Note that Zones II through VIII fall into the straight line portion of the curve The straight line portion of the curve represents a direct relationship between ex posure and density In other words as the exposure increases a correspon ding change in density occurs For every stop of exposure you add to the initial print exposure you will move up the zone scale by one zone For every exposure stop you subtract from the initial print exposure you will move down the scale by one zone We know that a light meter reads Zone V There fore on film an area of the image that falls into Zone V will be rendered as Zone VI when the expos
82. he higher zones in the detail area will function more as highlight or accent areas than detail carriers Regardless of the use you select for Zone III it is a conscious zone In good photography it seldom just happens You determine what scenic ele ments must contain detail in the shadows and place that area in Zone III Zone III is used as the base level for considering proper exposure This is because no matter how you finesse the development if you have not ex posed to record the shadow detail it will not appear in the negative For this reason we commonly use Zone III as the metering zone for dark tone me tering and as one of the end points of average value metering see page 43 This is difficult for beginning photographers who often meter the darkest area in a scene rather than a dark area with sharp detail Zone IV Dark Middle Gray Zone IV is a transitional zone that is full of detail The tonal change from shadow to lightness starts at Zone IV The progression through the two transitional zones IV and VI are very impor tant in determining the contrast feeling of the photograph If the transitional zones are minimized the image will look contrasty Though we must attend to how Zone IV functions it is not an issue of the amount of Zone IV in the picture but how the zone helps transition from the shadows to lighter tones Some photographers use this zone for dark tone metering By choosing a tone only one stop below middle gray th
83. highlight top right point and shadow bottom left point limits and tonal compression of the image OUTPUT There are two basic options for outputting your digital images The first is an online presentation e g on a website or e mail attachment or archiving your images on CD or DVD When sharing digital image files or on screen 122 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY oe E E i Top left In CS3 the Exposure control works as it does in CS2 The Fill Light control replaces CS2 s Shadow control it also holds constant the highlight point allowing you to adjust the shadows in the image The Brightness Contrast and Saturation controls in CS3 function the same as they did in CS2 Top right The yellow lines have been drawn in to indicate where the ends of the curve are moved to maximize the use of the curve When the point on the s position is moved up to about the 7 s level and the point at the 1 s position is moved downward the image is changed to the final product Above To adjust the curve to maximize the output of an inkjet printer move the end points 5 percent as shown by the red line Facing page The final image after proper exposure and image adjustment for the previsualized image There is detail in the surf and rich deep tones are visible in the rocks Photo by Glenn Rand s 4 i b oat a a a a Pan P s f ay ies images with your cli
84. ight has thresh olds and maximum limits based on the exposure given Realizing that we see a different dynamic range than the film or image sen sor records helps us greatly This ability to transition from perceiving the world as it appears before our eyes to visualizing it in terms of how the film or image sensor will record it is one of the most important yet difficult parts of the Zone System We need to look at our scenes in terms of the tonal qual ities that can be reproduced in our photographic process rather than just mar veling at the glories of the scene This is previsualization When looking at a scene we will try to normalize the tonal range This means that our perceptual system holds things to what we know as well as the reality of the tonality that is actually there In this way we tend to see light in VISUALIZING THE SYSTEM 47 most scenes as normal But in the photographic process there are several other concepts that can be seen as normal There are the standards set by the ISO International Standards Organization and the manufacturers These define the slope of the straight line portion of the film establishing sensor or film speeds and establishing specific values for the outcome of the process The process of exposing and processing the film is controlled and this is the concept that is used to establish the film speed We will use this later to es tablish working speeds for the Zone System There is a limit to th
85. image l Enter the EI into the meter Use the EI determined for the sensor and enter it into the meter or camera s metering system 2 Determine the highlight Read the brightest point in the image that you will want to have detail This will be the last tone below white Zone IX Your image editing software will allow you to open up darker tones but cannot open up overexposed areas For this reason exposing for the highlights is critical 3 Determine the shadow point Meter the darkest point in the image that below which it is acceptable to lose shadow detail 4 Determine the capture dynamic range Calculate the difference between steps 2 and 3 5 Place the exposure If the dynamic range is twelve stops or less the exposure is within the capture capabilities of the sensor Under these conditions the high The image on the left was taken using an incident meter reading f 11 1 125 and the image on the right was exposed using highlight exposure adjustment f 22 1 125 The histogram for the left image shows a large amount of pixels at or above the maximum exposure with little in the dark areas of the image The image on the right has a histogram that shows all but a few pixels falling between the extremes of the exposure a small white spike caused by the reflection of the sun This means that the image on the right has the ability to be processed to give tones throughout its captured dynamic range While
86. ion of the light shown in the flare This diagram depicts the interrelationship of the flare curve film curve and paper curve We can see how light from the scene is translated by the film and reproduced in the print At first glance it is obvious that the film curve is turned 90cedegrees counterclockwise Following any tone hor izontally from the flare curve to the film curve shows the effect of the light during exposure The point at which the tonal value intersects the film curve represents the effect of development on the tone Moving vertically from the intersection on the film curve we arrive at the paper curve The vertical line represents the light coming through the negative used to expose the paper The point where the vertical line from the film curve intersects the paper curve represents the exposure ef fect of the paper in the enlarger From the intersection on the paper curve we again move hori zontally to find the tone reproduced in the print 48 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY The printing of the paper can only happen within specific limits In the diagram above the char acteristic curve is shown in red and the blue lines show Dmax and Dmin The green vertical lines define the limits of the light that will show tonal variations in the print from the negative While the negative may provide tonal variation above and below the limits in this diagram as shown by the black rectangles light v
87. istic curve For this purpose we will need to make the curve This requires a reflection densitometer and a step wedge A step wedge is a printed series of density increases in regular steps from transparent to opaque Step wedges come in divisions of 0 10 or 0 15 den sity changes The density range of the step wedge is ten stops of exposure Density is measured in log units Log 2 0 30 Since our photographic system works on a 2 1 basis 0 30 equals one stop This means that a ten stop wedge ranges from a clear area 0 0 on the den sitometer to the most dense area 3 0 on the densitometer The 0 10 den sity step wedge is divided in 1 3 stops and the 0 15 is made up of 4 stops Either will serve our purposes Making a characteristic curve for paper requires us to print the step wedge on the paper in the manner we will use for our final printing Most will use an enlarger so the step wedge will be used as a negative and a print will be made Exposure of the print needs to achieve at three steps that are maximum black and three that are paper white We will use the print of the center por tion of the step wedge while ensuring pure black and pure white Once we have printed processed and dried the paper in a normal and standard way we will use a densitometer to read the reflective differences in the printed step wedge The numbers represent the density of the print These numbers are then graphed to create the characteristic curve The
88. ity of Michigan Since the early 1980s his extra academic research has included computer based imaging As a consultant Rand s clients have included the Ford Motor Company Photo Marketing Association Inter CHRISTOPHER BROUGHTON Christopher Broughton earned his BS and MS in professional photography from Brooks Institute in Santa Barbara CA where he served as Director of Laboratory Operations while completing his Masters of Science degree Prior to becoming a full time faculty member at the Brooks Institute in 1996 Broughton also served as faculty for University of Pitts burgh s Semester at Sea program He has authored ar ticles in Petersen s Photographic Outdoor Photographer PC Photo and Studio Photography amp Design Magazines and has been a featured lecturer for Hasselblad USA and Eastman Kodak Broughton s black amp white photogra phy is exhibited and represented by Art Matters in Long Beach CA Robin Fold of The Golden Orb CA The Griffin Gallery in Venice Beach CA and the Silver Light Gallery in Carmel CA DAVID RUDERMAN David Ruderman has been making photographs for many years and has studied with well ABOUT THE AUTHOR national the Ministry of Education of Finland and many other businesses and several colleges As part of his con sulting for the Eastman Kodak Company he traveled and lectured on how to maximize Tmax films when they were first released Black amp white photographs by
89. king Whether with film or digital photog raphy previsualization is a prime element for success in image making To accurately previsualize the image and create a print that meets our needs we need to understand how the various parts of the digital capture and output process can be manipulated and controlled ISSUES FOR DIGITAL PHOTOGRAPHY IN A ZONE SYSTEM APPROACH What are the constraints within today s digital photography that we must consider First and most important is the white level capture limit for digital sensors Whether a charged coupled device CCD or a complimentary metallic oxide semiconductor CMOS the sensors have a firm maximum range of light that they can record When the top level is reached the sensor stops accepting light at the maximum or the light energy spreads to adjacent pixels this is called blooming Once the limit is reached no difference be tween a fully exposed pixel and an overexposed pixel can be determined With the white limit reached all pixels at and above this limit will record white with no detail Though some photographers believe that using the raw file format THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY 107 allows this to be corrected in post capture the problem of overexposure can not be corrected in digital photography The second consideration is the dynamic range the sensor can capture The dynamic range can be defined as the difference between the brightest white that is not o
90. king the test print with the step wedge as explained above you can use a visual determination of where there is a change from black to white to define the extremes of the paper s exposure Once you have printed your step wedge look carefully and determine where there is a visible difference between the blacks at one end of the series of steps You need the number of this step Then do the same thing for the lighter end of the printed DEVELOPMENT 55 step wedge At the lighter end select the step with the first hint of tone darker than paper white and note the number of that step At this point in the visual process you have the numbers for the steps that approximate Dmin and Dmax for the paper For this information we will need to convert the step numbers to an exposure range for the paper This is done by taking the difference between the two steps just identified and mul tiplying by 0 15 if you used a twenty one step wedge or by 0 10 if you used a thirty one step wedge Though not as accurate as using a densito meter and working through the sensitometry of the paper this method will give you a good approximation of the paper s exposure range THE FILM As we saw in the last chapter different developing times for the film allow us to adapt to various lighting situations But we dealt only with general condi tions of expansion overdevelopment and compaction underdevelopment However there are many more potentials If we use a si
91. l 16 bit capture As explained above this is not the case and actually is a division of the light captured and trans ferred to the converter in 16 bits per channel In the Camera Raw dialog box you ll find sliders that can be used to ad just the exposure shadows brightness contrast and saturation These con trols will help you finesse the light levels in the image and produce your previsualized image Note that the adjustments should be made with the auto box above each slider deselected The Exposure slider can be used to adjust the dynamic range in the image Moving the slider to the left increases the number of darker tones in the image and moving it to the right edge increases the overall image brightness The Shadows control anchors the highlight point but allows you to ma nipulate the dark tones in the image Since digital files are ideally exposed for the highlights this will be a very effective control The Brightness slider anchors the shadow point but allows you to manip ulate the brightness in the image The Contrast slider adjusts the overall distribution of the light captured in the image file and allows us to maximize the output tones The Saturation slider has little effect on the light captured in the image Moving the slider toward the left end 100 will produce a grayscale image Moving the slider to the right end will gradually boost saturation You will need to experiment to find the best controls for your expo
92. long tonal range then we can make a simple adjustment to the development time that will produce a negative that is closer to our need for the paper Likewise if we determine that the light from the scene has less tonal range than the paper requires we can make another simple adjust ment to develop the negative to match the paper s ability to accurately rep resent the scene EXPANSION COMPACTION As we just saw when all the parts flare film and paper are in sync the negative will provide what is needed to represent our previsualized tones But as just mentioned the exposure needs to be within the limits for nor mal for the system to work We can make small adjustments in development to control the negative s contrast if the light is not normal The idea is to over or underdevelop to make the negatives meet the needs of the paper Understanding the development of silver halide emulsions is VISUALIZING THE SYSTEM 49 key to being able to change the development to create negatives that fit the paper s exposure range Development has a greater effect on highlights than on shadows As we in crease development there is a buildup in density with more density in areas of greater exposure As the film curve shows as you give more development there is an increasing spread of the two curves as you get farther from the toe The opposite is also true with controlled underdevelopment the negative loses
93. ls the amount of light that can be passed to paper The film s devel opment functions as a dependent variable In the Zone System we are striv ing for the great print by adapting to the changing light of the scene To make the system work we need information about what the paper s range requires and how to make the film produce that range This means we must test the paper and film beyond the levels we have discussed to this point We will use densitometric information to define our paper s constant value and the effects of the film s development to adapt to changes in the light environment THE PAPER Because the Zone System is based on a group of interrelated standards we need to stick with our chosen or tested standard To find the paper s standard DEVELOPMENT 53 for exposure we will either need to create characteristic curves for our paper or use the ANSI standards for the paper with filtration for multigrade paper If we choose to use ANSI standards we will need to select a specific value for the paper s exposure range from the range given by ANSI ANSI GRADES EXPOSURE RANGES Print Filter Description Cold Light Condenser Very Soft 1 41 gt 1 09 gt Soft 1 15 1 4 86 1 08 Medium 95 1 14 71 85 Hard 80 94 60 70 Very Hard 65 79 49 59 Extra Hard lt 64 lt 48 To be as accurate as possible we will want to find our exposure range for the paper by analyzing its character
94. ment is used for compaction If we determine that the light produces more or less tone than normal light we can decide what kind of development to use to ensure the negative has the tonal range needed to produce a good print Two non normal lighting conditions are very common The first is overcast skies Overcast skies diffuse the light and shorten the range of tones in the scene by putting light into the shadows and not providing a specular light source to give bright highlights Generally for overcast situations expansion overdevelopment aids in making negatives that encompass full tonal range The second non normal lighting condition is bright sun In this scenario you need to com press the long tonal range through compaction underdevelopment Time temp agitation and developer dilution or concentration affect the rate Though you should test the development to get accurate development times and chemical dilutions strengths for both expansion and compaction you can use the following guidelines as a starting point Expansion 120 percent of normal development 20 percent Compaction 88 percent of normal development 12 percent Sometimes it is very difficult to control development through time when your times are very short because of the possibility of uneven development On the other hand when your development times are extremely long there is a possibility of a large temperature drift or death by boredom It is
95. milar idea of what we just did for paper we can determine the range of light that will work with a specific development PLOTTING FILM CURVES Instead of plotting one curve we need to generate a family of curves that de pict a variety of developing times You can expose with a sensitometer en larger or camera You can use the same step wedge that was used for the paper but this time it will be exposed onto film Because of the small size of the film it is best to contact print the step wedge directly on the film You will need to test the ex posure if your lighting source is an enlarger You will need to expose at least five separate pieces of film While they are all exposed for the same effective ISO their developing times will vary A sensitometer will give the most consistent results but an enlarger is a good The film curves below show the effects of development times from five minutes to twelve minutes The six minute development curve yellow is shallow and shows the effect of capturing light over three stops more light than is normal N 3 development The cyan lines show the effect of a near normal development time of nine minutes N The twelve minute curve blue lines shows the effects of a development to deal with two stops less light than normal N 2 ANTT ma tet i wiv i NAT BYGNS ARIEL TELL Bawa y UTADA TTT Mm TT NLT TL ir 4 __ _ i ee _ _ EE m a rm
96. mize our capture When working with digital capture we need to test our sensor s exposure index EI Film is more tolerant of some overexposure than is the image sensor so we will test the sensor s ability to tolerate overexposure The test for finding your image sensor s optimal EI is not very different from the film speed test used to find the optimal ISO setting To run the test you will need the following 1 A meter designed to meter the light in the scene e g an incident light meter or you can take a reflective meter reading of an 18 percent gray card 2 A test target that consists of a white 18 percent gray and black area that will be large enough on the image to measure in imaging software These can be overlapped separate cards 3 A model The model should be wearing a textured white shirt or sweater If need be a piece of white material with heavy texture ribs or cabling can be draped over the subject s shoulder 4 The camera must be in manual mode so that you can adjust the shutter speed and aperture and set it to capture raw files To ensure the test is properly conducted complete the following steps l Find or create an evenly illuminated scene with an even solid dark background If there is a bright background or backlighting the test will be inaccurate 2 Place the card s on a stand near the model s face Accuracy will only happen when the gray black and white cards are parallel to the sensor
97. n sity or where the film curve turns upward and the shoulder rounding off at the top or the highest density of the negative All densities in the negative below Dmin will reproduce in a print as black and all tones above Dmax will reproduce as white The point where the toe ends and the curve becomes a straight line is known as the speed point This represents a value used to establish our exposure index and has a value of FB F 0 10 In the film curve chart below the red line indicates the densities of the negative the hor izontal dashed line at the bottom represents Dmin the horizontal dashed line at the top rep resents Dmax and the zone scale indicates which zones will be created by various densities in the negatives The densities shown as the portion below the Dmin line represents the end of the tone and black in the print the density portion above Dmax will reproduce as white The photographic printing paper curve has the same components as the film curve though we do not use a measure of speed point Thus the ANSI standard for Dmin repre sents white or paper base B F 0 04 and Dmax is 0 9X the maximum black that is seen as black eram Provan her ee es ee a an a A A A A EES td Above Film curve with zones Left Paper curve with zones 30 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Because the sky reflected as dark middle gray in the smooth water
98. n relation to the subject This type of light is characterized by a high contrast range In other words direct light produces bright highlights and sharp dark shadows In the studio specular light may result for example when lighting your subject with a single light with little ambient light filling in the shadow areas there is a high dynamic range In outdoor work specular light results on a clear day when the sun s light hits the earth in parallel rays To envision specular light think of the tiny hot spots you might see on a car s chrome bumper on a sunny day UNDERSTANDING LIGHT 27 Diffuse light is soft in nature and is characterized by softer shad ows which in some cases may even disappear In studio work diffuse light is often achieved by passing light through a large transparent material placed close to the subject A softbox is a pop ular diffuser however its proximity to the subject is key in deter mining the quality of light that will result Even a softbox can produce harsh light on the subject if it is positioned far away Soft light may also be created by using a series of lights to illuminate the subject When working outdoors cloud cover humidity direction of the light altitude and particles in the air affect the quality of the light Humidity fog and rain for instance can affect the path of direct light softening the effects of the sun and reflected light in the scene and lowering the contrast ra
99. ne meter reading f 32 3 Area metered for exposure as Zone III Photo by Glenn Rand Below This image shows the effect of the N 2 development on the scene s tones wji MN TTN is Gh AH fe amp fh Be re Ae ZONE CONTROL AS AN OVERALL CONCEPT Particularly when using roll film and in very consistent light such as clear skies in the desert we can use an overall approach to the Zone System This method holds the light as unchanging during the photography session The assumption for an overall consistent lighting means that the development for all exposures will be considered to be the same This is because the inde pendent variable of the light remains at the same measured values In the overall approach we will meter the extremes of the light and use that reading to determine what development will be needed We look at the scene and meter the darkest area Zone II below detail We select this zone because it can be tough to differentiate between Zone 0 and Zone in the scene Also we want Zone 0 to fall below Dmin on the film For similar rea sons we select the lightest area of our scene and assume it to be Zone VIII Therefore we can compare our meter readings of our darkest and lightest against our normal light range of seven stops Let us look at two examples that will show how the overall method works Note For all examples we used Tmax 100 developed in D 76 1 1 at 70 F Example 1 Conditions of the scene
100. ng or burning may be needed in which areas At this point you cut the paper into pieces that will cover the areas you have determined need adjustment Next you will place the cut pieces of paper in the printing easel in the areas where you will adjust the exposure with ei ther dodging or burning If you will be burning the area after giving the pieces of paper the base exposure give the added exposure you expect to use Repeat this process with more and less time than you estimated for the burn ADVANCED PRINTING TECHNIQUES 99 After processing the paper the same as the base exposure print you can place the various pieces of paper on the print to see the effect that will be created without using an entire piece of paper for each test For dodging you subtract exposure from the pieces of paper that cover the areas that need to be lightened In this situation you can use your dodging tool and count the dodge or you can subtract the time differential from the base exposure and expose the pieces of paper After processing the paper you use the same method discussed above for determining the amount of expo sure to reduce the exposure of the print Of course consistency is one of the keys in creating great prints With dodging and burning there are several tools we can use The first is a metro nome Some enlarger timers have an audible tone that can be turned on to assist counting If your timer does not have this capability you can purchase
101. nge Tabular grain film such as Tmax shows reciprocity failure differently The ta bles on page 90 show the exposure and development changes required by reciprocity failure To accurately determine the way reciprocity failure affects any particular film you will need to do extensive testing USING RECIPROCITY FAILURE FOR EXPANSION Because we need to change exposure and development with reciprocity fail ure we can use this knowledge to make N exposures If the film is devel oped normally when it requires decreased development because of reciprocity it will perform as though it is photographed in normal light ranges with N development The following chart provides information on using reciprocity failure for expansion photography IN CAMERA CONTRAST CORRECTION 89 To take advantage of reciprocity failure for N zone exposures you will want to force your system into long exposures This can be done with small f stops on the camera and or filters Be aware that with these long exposure times motion effects can be a problem KODAK TMAX 100 Meter Reading Exposure Comp Contrast Effect 30 sec 55 sec N 5 1 min 2 min N 1 2 min 5 min N 2 4 min 12 min N 3 8 min 30 min N 3 5 15 min 1 hour N 4 CONVENTIONAL GRAIN FILMS Meter Reading Exposure Comp Contrast Effect 4 sec 8 sec N 5 15 sec 1 min N 1 1 min 5 min N 2 4 min 24 min N 3 Left Photo by Glenn Rand Facing page With the
102. nge in the image On an overcast day for instance the sun lights up the clouds and they transmit the light to the earth s surface from all across the sky cre ating many angles of light In the natural landscape light com monly becomes more diffuse when sunlight reflects off light toned surfaces such as snowfields sand light colored rock walls or even light colored trees These surfaces not only reflect the light into Photo by Glenn Rand the shadows but also diffuse the reflected light because they are textured and often change the color of the light The specular diffuse nature of the light should not be confused with the intensity of the light Intensity of the light deals with how much light is illu minating the scene not its specular or diffuse nature While intensity affects how exposure is made it does not affect the quality of the light We must also be careful not to confuse the subject contrast range with specular diffuse light The difference in reflectivity of various parts of the scene creates the subject contrast range If there is a large subject contrast range then specular light will only expand those differences while diffuse light can only reduce the apparent differences depending on how each tone was created Sweet Light Another type of light that is very interesting to many pho tographers is what is called sweet light On clear days this light exists from about one half to one hour before sunrise to
103. num ber of steps on the wedge is plotted on the horizontal axis of the graph and the corresponding density measurements are graphed on the vertical axis The enlarger type condenser diffusion or cold light along with paper grade or filtration for multi contrast paper will affect the exposure range Since we want to hold the paper as a constant these variables need to be kept constant we must not change the paper grade filtration or enlarger type 54 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY THE 0 10 DENSITY STEP WEDGE IS DIVIDED IN s STOPS AND THE 0 15 IS MADE UP OF 1 2 STOPS Cr PERCE TEE See EE eo TF na i i T We are interested most in one piece of information that we will get from eee ee IE the curve the exposure range of the paper To find this we first need to es tablish the Dmin and Dmax To find Hotton tie 7 a ie uve I these points on the curve we will first work vertically We use the dense area of the step wedge that printed as a paper white reading you should use at least three steps that print as white This is the paper s base plus any fog created in the processing This will be used to determine Dmin Dmin is calculated by taking the density value of the white base plus fog B F and adding the ANSI standard constant of 0 04 The paper characteristic curve shows the graphing of the densities from the printed step wedge If we take the value just
104. onal separation method approaches each exposure as unique Photo by Robert Smith WE USE THE CENTER VALUE OF EACH ZONE AS OPPOSED TO THE EXTREMES OF THE RANGE OF EACH ZONE Right Kauai Hawaii 1997 1 Zone VI reading f 16 2 Zone II meter reading f 2 3 Area metered for exposure as Zone III Photo by Glenn Rand Below Here we see the effect of the N 2 development on the scene s tone vij 1 i Mit il ii IA E E nr A Ar w ii ne om In this approach we meter any two tones within the Zone II VI range and use their tonal separation along with the previsualization of the final print to determine what development will be needed In doing this we tend to use the center value of each zone as opposed to the extremes of the range of each zone However you can use the extremes or any portion of the zones by using fractions of the zones in your calculations Instead of using a set number as normal we use the previsualized zones for our two tonal areas We say that the numerical difference between previsual ized zones is normal Unlike the overall approach we do not expand or com pact development for the effect on the whole negative Rather we use development to achieve a desired difference between our previsualized areas of the image that will be translated into specific zones Let us look at two examples that can show how the tonal separation method can work Note Both examples use Tma
105. otential light that might reach the film The green lines down from each line show how much of the grayscale is captured at a given development The orange line indicates normal development the cyan line shows overdevelopment and the red line shows the effect of underdevelopment Because Dmin and Dmax stay the same this diagram shows that overdevelopment gathers the least light represented by the grayscale and the underdevelopment captures the most OVERDEVELOPMENT EXPANDS TONES THAT THE NEGATIVE WILL PROVIDE Rotating just the film curve 90cedegrees clockwise to have the horizontal axis represent exposure we have the usual presentation of the film curve In this view we can see that the steeper curve relates to the smaller scenic tonal range On the other hand if we underdevelop and get a shallower curve with more tonal variation from the scene we will make the negative meet the ex posure range of the paper When we overdevelop or underdevelop to make the film record the non normal light we call it expansion or compaction also known as contraction Expansion is used for processing photos taken in light that does not have as much tonal variation as normal Overdevelopment expands tones that the negative will provide Where there are more tones available than normal light provides we need to compact or compress the negative to reduce the tones so they will fit within the exposure range of the paper Underdevelop
106. preexposure also known as flashing or presensitizing the film Flashing is a common process in print ing but can also be used in the capture stage This process presensitizes the film up to its threshold The purpose of preexposure is to expand the sensi tivity of the film to better record deep shadow details Preexposure is not IN CAMERA CONTRAST CORRECTION 85 suited for digital photography since it may result in overexposure or create unwanted noise A closer look at the toe of the characteristic curve of film shows that there is density change below Dmin Adding a small amount of exposure before or after taking the photograph will shift Dmin to open up shadow details The extra exposure will have a noticeable effect on the shadow detail but will not impact the highlights The process is to use an even tone and underexpose the film just below the threshold of the film This exposure added to low levels of exposure provides enough density to be printed In the field or with roll film a gray card or a piece of translucent white Plexiglas can be used to provide the even tone The gray card needs to be positioned in front of the lens so that it completely Photo by Christopher Broughton Photo by Christopher Broughton covers the frame It should be out of focus and in even light A meter read ing of the gray card is taken and then the camera is stopped down four stops before flashing the film When using the Plexiglas
107. proach we use a light meter and read the dark area of what will be our picture then pick the brightest highlight and measure that area The difference should be seven stops The tonal separation method is another way to measure the light We can pick any two zones between II and VIII and these should have the same separation in number of stops as our previsualized image Regardless of the method we use to define the light it will be the act of estimating the zone of the light and measuring it that will have the greatest impact on the photo graphs we make With the preparations we have made through the testing and our previsu alization we find that the Zone System is not complicated With the infor mation generated we need only five procedural steps in the field to make photographs with the Zone System A key consideration is that we need to find a way to compare the light of the scene to the information we generated about development for various light conditions When we see the scene we wish to capture we start to visualize how the light in the scene will be rep resented as tones in the final print We might use a zone ruler or rely on our memory of the print zones Prior to the first procedure comes previsualization of the image This cru cial portion of the process relates the scene in front of our eyes to the print that we will produce The rest of the steps are as follows 1 Determine the light within the entire scene Measure the ex
108. puter screen a raw file provides the best representation of the captured light POST CAPTURE PROCESSING When the image is captured without overexposing the white level image editing software can be used to open up the shadows and create a photo graph that matches the previsualized image Note Both CS2 and CS3 feature raw file conversion capabilities In the paragraphs that follow we will look at how Photoshop CS2 is used to make post capture enhancements and will then outline the way the process differs when using CS3 The process is straightforward The image should be processed in 16 bits per channel In Camera Raw use the pull down menu to the right of the ee H a aA ie LIME td ragian e 2 ia Sien Se Crin mEn Ek The yellow highlighted portion shows where the selection for depth is found in Camera Raw THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY 119 Depth field to set this preference In Photoshop CS2 go to Image gt Mode gt 16 Bits Channel Selecting this setting does not expand the dynamic range of the image but prevents the loss of image detail because the image has been compressed into 8 bits per channel when opened from the captured dynamic range When the image is open in Camera Raw the light resembles that captured in the scene Regardless of the exposure control applied it will be spread as near as possible across the 16 bit range This means the histogram for the image will appear as a file with a tota
109. r selected film The testing process involves a few simple steps Metering Taking a light meter reading allows us to understand the way the light in our scene will affect our exposure It is a critical step in creating a 10 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Above Photo by David Ruderman Facing page Photo by Robert Smith SHUTTER SPEED CALIBRATION IS THE FIRST STEP IN STANDARDIZING OUR PHOTOGRAPHIC PROCESS negative that will allow us to ice a print that matches our previsualiza tion of the subject or scene Light meters can measure incident light light falling on the subject or re flected light light that bounces off of a subject or element in a scene For our purposes using a reflective meter is the best bet There are three types of reflective meters The most common type is the TTL through the lens meter which is built into a camera When using the Zone System such meters can be useful as measuring tools not automatic ex Photo by Christopher Broughton Photo by Christopher Broughton BEING AWARE OF THE SUBTLETY OF THE LIGHT IS WHERE THE ZONE SYSTEM COMES ALIVE posure controls To use a TTL meter set it to spot mode or place it close to the reflective subject rather than taking a reading from distance Handheld av eraging meters are yet another option The downside to using them is that you must be able to stand close to the subject you are metering so
110. raduation on mass manufactured grad IN CAMERA CONTRAST CORRECTION 81 oe i k We F oh Lae ye Fatt hy B i P T i j EF b E j a i 4 A Sy ot T uated filters have straight or regular split fields and do not always fit the de sired contour of an image Another type of filter that is used in black amp white photography is the interference filter There are both diffusion filters and polarizing filters Dif fusion filters put material in front of the lens that breaks up and softens the light A polarizing filter allows light to more easily travel through the filter if its wave form is parallel to the micrometallic lines on the filter This allows for the elimination of or increase in the brightness of light coming from reflec tive surfaces The polarizer darkens blue sky and increases cloud separation at some angles It will also eliminate reflections from reflective surfaces This filter allows light to penetrate some haze by reducing reflections from at mospheric particles thereby resulting in images with higher contrast When a polarizer is combined with a yellow filter it increases cloud separation with out extreme reduction of shadow exposure Any time we put a filter between the scene and the film we need to in crease exposure This is known as a filter factor You should refer to the in 82 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by Glenn Rand THE POLARIZ
111. re When using this method be sure to choose the area of the scene containing detail Zone III that is important to your photograph Some photographers choose the darkest area in the scene as their dark tone When they do this they over expose by two or three stops This is a very common mistake Highlight Detail Metering While not as common as dark tone metering some photographers prefer to meter highlight details In this method you meter the area in which you want to show highlight detail and adjust the ex ZONE PLACEMENT 43 posure by opening up by two stops This is a preferred method for digital photography Average Value Metering Some scenes we encounter will be predom inantly comprised of light tones or dark tones In such a case we can use average value metering to make good negatives In the previous chapter we learned that Zone III is the darkest area of the scene where we can see sharp detail with full texture Zone VIII is the lightest area of the scene where we can see sharp detail and full texture Therefore if we can control these areas we will create an exposure that contains both highlight and shadow detail Prior to metering and exposing for the image we must previsualize the way the important highlight and shadow areas of the image should ap pear in the final print These areas of the scene will become Zone II and Zone VII in our final print Note that in order to use this ex posure m
112. re using the Zone System to finesse your capture and development and make the scene appear in the print as it did in the scene 24 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Photo by David Ruderman THROUGH EXPOSURE CONTROL WE CAN MANIPULATE THE LIMITS OF THE FILM IN OUTDOOR SCENES MOST OF THE LIGHT THAT YOU WILL USE TO MAKE PHOTOGRAPHS IS REFLECTED LIGHT Photo by Glenn Rand QUALITIES OF LIGHT Reflected Light To optimize our black amp white photography we must un derstand the way the quality of light will affect the scene and ultimately the photograph In outdoor scenes most of the light that you will use to make photographs is reflected light Several things affect the reflected light that we see and capture when pho tographing our subject The qualities of the subject for instance whether it is light and smooth or dark and textured affect the way it will be recorded on film Dark objects reflect less light than light objects The angle of inci dence of the light and the direction in which the light is reflected from an ob ject s surfaces also impacts the way the scene is recorded For instance a mirrored surface will reflect almost all light striking it but if the reflection is pointed away from the camera then little light will be recorded Reflective subjects also affect the appearance of nearby scenic elements For instance when light is reflected off of a white wall it can s
113. roup exhibitions ABOUT THE AUTHOR 5 d H a2 J a RES T B ma i ir ae E TS rh INTRODUCTION As photographers we see the effects of light falling on our subjects and are drawn to create images so we can share the visual excitement However in order to best communicate our vision to viewers of our photographs we must rely on some tools and processes that allow us to effectively convey our impressions The Zone System is one of these tools It allows us to precisely record our visual impression of the world and tell someone else what we saw Facing page Photo by Glenn Rand 1n the most beautiful of visual languages the language of black amp white Below Photo by Christopher Broughton photography THE CONCEPT The Zone System looks at the photographic process with the finished prod uct in mind Putting consideration of the print at the beginning of the cre ative process means that the end of the process is as important as finding the subject for the photograph This idea is known as previsualization To present viewers with a print that matches our creative vision we must have a clear idea of the way that light affects the scene and the way the visual information in the scene will be recorded on the negative We must be able to control exposure to ensure the widest range of tones from black to white measured in zones in this system and capture detail within all important areas of the scene When we capture
114. s With digital sensors the dynamic range is fixed and ranges between eleven and fourteen stops depending on the type of sensor and manufacturer This means that film can be used in light conditions that are beyond the capture capabilities of digital photography Another major difference between using the film based and digital Zone System is that a digital approach can capture color images When working with film on the other hand the Zone System can only be applied to black amp white capture because color film when overdeveloped or underdevel oped changes color balance This restricts our ability to control contrast In digital imaging colors that fall outside of capture or output limits are called clipped The clipping or cutoff point in capture occurs when 1 the light in the scene is too low to be recorded as anything other than noise or 2 the brightness level at the high end was too great for the sensor to fully capture In output the clipping points are where the printer can no longer differentiate tones near black or white For example if you are printing your image using an inkjet printer that can only reproduce a seven stop range then image detail beyond the printable range will be lost THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY 111 DEFINING THE PARTS OF A DIGITAL ZONE SYSTEM Earlier in the chapter we learned that previsualization is key to a successful digital image just as it is when using film There are several
115. subtle tonality to the highlight areas when working on lighter areas of the print If the burning is used to darken an already dark area a magenta filter 4 5 will maintain more of the shadow detail rather than block the dark areas up with the added exposure FLASHING As discussed in the previous chapter we can change the way low light expo sures affect film by giving an extra exposure to an even tone under the level that will expose Dmin This preexposure process is more common in print ing and is known as flashing The preexposure of film works on shadow de tail but in the print it affects the highlights By adding a small amount of light just below the tonal threshold Dmin to the paper we move the ef fective exposure point of Dmin white level to a lower amount of exposure This expands the exposure range of the paper only in the area of Dmin Flash ing has no noticeable effect on the detail or dark zones in the print Flashing can be used either for overall or local control To determine the amount of flashing that will be needed to bring out added highlight detail you will need to do a test strip with only flashing ex posures To do this take the negative from the enlarger so that you are print ADVANCED PRINTING TECHNIQUES 101 ing with white or filtered light While flashing can work with any filter flash ing acts contrary to the higher filters 4 5 To increase the effect of flash ing a lower number filter 0
116. sunrise and also from about a half hour to an hour following sunset This is dependent on the sky condi tions time of year and the landscape This light is very long in contrast range even though the light is diffused The brightest portion of the sky is around the horizon and the light lacks strong directionality Because the light is highly diffuse and not strongly directional the light penetrates into shadows opening them up and allowing exposure of large areas of the scene that might otherwise be overlooked as potential picture areas Now that we understand the basics of light we can begin to analyze how light is recorded in the negative and how we can manipulate exposure and de velopment to create the visual effects we desire in our prints 28 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY DIFFUSE LIGHT IS SOFT IN NATURE AND IS CHARACTERIZED BY SOFTER SHADOWS CHAPTER THREE THE ZONE SCALE The zone scale also called the grayscale or zone ruler is perhaps the most recognizable component of the Zone System It is a visual tool comprised of a series of eleven tones labeled Zone 0 through Zone X ranging from pure black to pure white Once we ve metered key areas of our subject we can use this tool to previsualize the tones in the scene as various print densities Note Some Zone System practitioners use a ten zone scale labeled Zone 0 through Zone IX Either scale can be used to achieve good photographs
117. sure preferences The following list outlines one of the general steps required to maximize the image Set the Exposure slider to 0 so that the image exposure appears close to the way it was captured Note that if the majority of the histogram data is located predominantly on the right highlight side of the histogram or on the left shadow side of the histogram the image will be too light or too dark and an exposure adjustment will be required 2 Adjust the Shadow slider until the data is close to but not at the extreme left edge of the histogram Because the right end point of the tonal range shown in the histogram is anchored moving the slider will only allow you to adjust the shadows Ww Adjust the Brightness slider to achieve the desired results in critical areas Because the left end point of the tonal range shown in the histogram is 120 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY INCREASED CONTROL The Shadows Brightness and Exposure sliders are particularly handy for opening up detail that has been underexposed to reduce the chances of overexposing the image highlights THE SATURATION SLIDER HAS LITTLE EFFECT ON THE LIGHT CAPTURED IN THE IMAGE The image matches the previsualization There is detail in all areas of the image including the star created by the sun s reflection diffracted by the iris in the lens While the sun s orb is beyond the sensor s sensitivity there
118. this zone Once again in this tran sitional zone we need to attend to how this zone functions within the image more than the amount of the zone in the picture Since bright areas appear to advance in a print the highlight and accent areas in this zone are very attractive to the eye Note that Zone VI serves as the base of high key imagery This zone is also used in substitution metering When photographing Cau casian portrait subjects you can meter the palm of the hand instead of a gray card and open up one stop to create an effective image Zone VII Highlight Detail At the light end of the detail area is Zone VII With a reflectivity of approximately 72 percent this is the last zone in which sharp detail will be visible Just as in Zone III for the image to func tion the detail in Zone VII is critical If the majority of detail falls in this zone the image will take on a soft light and airy feel This is why we often use higher key images to convey a romantic feel LITTLE KNOWN FACT We typically think of zones as consisting of a single tonal value because this makes it easier for us to quickly conceptualize the final print For example we think of Zone V as 18 percent gray However within each zone there is actually a range of re flectance values For instance Zone V ac tually spans reflected values from about 13 to 27 percent Seldom do we find naturally occurring high key images such as this one previsualized by D
119. tion Because bleaching is done after fixing the bleach can only act on areas of the picture that were blackened silver The reduction happens evenly across all tones of the image Reducing the image s density evenly throughout the print affects Dmin more than Dmax With the reduction of silvers in the print Dmin will be moved to the exposure value that created a light gray in the original print While Dmin shifts by reducing the total amount the effect on Dmax is hardly changed Dmax is 90 percent of maximum black and the effect of bleach reduction is only a 10 percent change With proportionally larger re ductions in the exposure value of Dmin than Dmax the bleaching increases the highlight difference from other portions of the print The visual effect of bleaching is to increase the contrast Bleaching can be used on the image globally or as a local control When bleaching is used on a print locally it acts like dodging for lighter areas To bleach a small area of the print you will want to work in a sink with a small hose or tube able to bring water to the area you are using to work on the print Whether using bleach followed by fixer or Farmer s Reducer you will need running water to control the area being affected by the bleach Place the print on a flat steeply inclined surface holding the flowing water from the tube just below the area to be bleached Then using a cotton swab or water color brush apply the bleaching solution to the
120. tiple 85 126 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY Exposure range See Exposure index F Field charts 76 77 File formats 80 107 113 119 JPEG 119 raw 80 107 113 119 Film 10 18 40 41 42 48 54 55 56 64 69 87 89 curve 40 41 42 48 54 56 64 intensifying toning negatives 104 ISO 48 56 62 64 speed test 10 18 Filter factor 83 Filters 16 21 42 54 79 83 Fixer 95 Flare 14 45 48 68 camera system 45 46 scenic 14 46 48 68 Flashing 85 101 2 Fog 36 46 55 G Gamma 40 Gradient average 40 Gray card 14 83 86 87 113 Gray scale See Zone scale H High dynamic range imaging 85 105 122 High key 34 Human vision 23 24 47 I Image sensor 48 107 10 Intensifying negatives 104 ISO rating setting 48 56 62 64 113 114 L Light 25 28 46 49 51 76 angle of incidence 25 diffuse 27 28 46 fill 76 hard See Light specular intensity 28 normal 49 51 overcast 28 46 51 main 76 ratio 76 reflected 25 27 soft See Light diffuse specular 27 28 51 74 113 sweet 28 Low key 32 M Matboard 14 83 Metering 10 13 41 42 44 115 average value metering 32 35 44 67 dark tone metering 32 43 112 115 highlight detail metering 43 44 115 incident 76 113 reflective 13 43 113 spot 13 83 target 13 14 TTL 87 Middle gray See Zone V N Noise 110 118 N values 60 64 67 70 71 88 90 118 0 Output C
121. tremes of the light This is done through average value metering In other words we will measure an area with the darkest shadow detail in the scene and an area with highlight detail We then count the stops between these two readings In this case we end up with two numbers the first is the num ber of stops representing normal light the second is the light s tonal range which is determined with a light meter 2 Next we need to find the normal N development You will take this information back to your darkroom after the photograph is taken When we calculate the development we will subtract the metered range stop range between meter readings from the light s normal range The nor mal light is seven stops including Zone II and Zone VIII If our meter ing in step 1 was six stops our calculation would be N seven minus measured six in this example Because 7 6 1 development will be N 1 3 We must adjust the exposure to ensure shadow detail We do this by ad justing the ISO in relation to the N value we determined in the second step This ISO needs to be put into the light metering system before going on to step 4 4 With the new ISO setting put into the meter take a light meter meas urement of the area of the picture that will be Zone III in the final MAKING PHOTOGRAPHS 67 image We need to be sure to expose for the shadows and develop for the highlights 5 Finally we must set the exposure This is done by
122. trigues visual artists In creating photographs we can communicate those things that engage and enlighten us to our viewers We can create a visual narrative that exceeds the reach of our spoken language We are all capable of seeing something interesting and unique but it is the effectiveness with which we communicate our vision that makes our work important An effective image should do more than present a likeness of the subject or scene Your images must have content Even the most carefully crafted communication is meaningless if the content has no real value Mastery of the Zone System then should enhance your communication it is not the end all and be all of that communication As you learned in reading this book there are four distinct aspects of the photographic process First and foremost is visualization of the image followed by the capture of images the processes required to create the print and finally the presentation The methods I use enhance visualization in the photographic process but do not replace it Because I have tested and own my processes and the tools used to carry out my vision my creativity is not hampered by concerns as to whether or not the image I previsualize can be made into a print By own ing and trusting the processes described in this book I am free to use my eyes and interpret the world for my audience The strategies involved in the image capture have become a seamless part of the c
123. trike another scenic ele ment opening up the shadows and softening the overall contrast in the scene Conversely a nearby dark row of trees can increase the dynamic range in the y lij UARA 4 1 7 Iii vil ni wy Eih Nk j i ea eee eet ed ee a ji g p p FIL EE WI g ji f 4 4 iM j Enrop miii b L eens 7 te A ee Facing page Photo by Glenn Rand Right Photo by Robert Smith LIGHT NORMALLY HAS A COLOR BIAS THAT CAN AFFECT THE INTENSITY OF REFLECTED LIGHT scene by absorbing more of the ambient light and keeping it from lightening up the shadows Even though we are capturing black amp white images the color of light in our scene can affect the final print Light normally has a color bias that can affect the intensity of reflected light At sunrise or sunset for instance light takes on a reddish cast that will not reflect as well from green objects as it will from neutral tones Similarly open shade without direct sunlight is very blue and reduces the reflectivity from yellow or reddish subjects Remember our eyes can adapt to changes in light allowing us to perceive colors as we expect them to be rendered Film cannot process this information in this way It sim ply records what is there Specular vs Diffuse Light Light is often described as being specular hard or diffuse soft Specular light is produced when a light source is po sitioned far from a subject or is small i
124. tter speeds There fore longer exposures will allow us to perform dodging exposure more ac curately shutter speeds of 1 2 second or longer will work well This method of dodging is particularly helpful for scenes that have bright skies The second way to dodge exposure is to repeat the exposure with and without the black card in place The amount of exposure used for the multi ples needs to be the same as a normal exposure Though this method can work in bright light it is better in more subdued light with need to only re duce areas outside the overall dynamic range of the scene Two notes of caution if you choose to use this method of dodging First the card will need to create a soft border image on the negative to success 84 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY THIS METHOD OF DODGING IS PARTICULARLY HELPFUL FOR SCENES THAT HAVE BRIGHT SKIES While the exposure was in progress a black card was brought down through the top of the lens s view Photo by Glenn Rand ETO O Cee Ora Garg Cw Above tThe left image is the underexposed bracket and the right image is the over exposed bracket The light image was placed in the background with the darker image lay ered on top with the opacity reduced A mask was applied to the foreground of the darker layer Right The final image shows the use of the lighter image to allow good detail in the shadow areas while the darker image
125. turally occurring light situation How ever if need be you can use a single toned target Because we need to pro duce a thin i e low density negative you will want to use a darker toned target like a gray card or a dark colored piece of matboard Whatever your choice make sure that the target is large enough to fill the frame at least 8x10 inches The lens should be set to infinity Focus is not an issue Meter the center and the four corners of the dark target before starting the test They should all read the same If they read differently then the target is not evenly lit Below Photo by Christopher Broughton Facing page Photo by Glenn Rand Location Photograph your target on the shaded side of a building or under a cloudy sky Do not conduct the test on a day when the sun is intermittently blocked by cloud cover If you use artificial lights note that tungsten lights will yield different results than sunlight You can compensate for the differ ence in the color of the tungsten light by using an 80A filter for the test Tripod Setting your camera on a tripod will allow you to keep the camera steady and eliminate the need to reframe the shot when creating a series of exposures Technical note Some cameras allow you to change the aperture setting in 1 3 stops some change in 1 2 stops and some change in whole stops It is im portant to understand how your camera s settings work before starting this test
126. ult is the number of stops of light from the darkest part of the scene to the lightest that will produce a negative that fits the paper at the development time for that curve With the information generated from each curve we now have a set of de velopment times and the subject brightness range SBR from the scene that each development works best with This is the foundation of our exposure system In Zone System terminology these developing times are referred to as N normal N normal plus or expansion and N normal minus or compaction development But how do we define N N or N First we need to define normal de velopment in relation to the light in the scene As was discussed earlier we know that reciprocity functions between Zones II and VII Because of the compression of the tonal difference at both ends of the zone scale we need to discount the light potentials of the outlying zones 0 I IX and X That is a difference of six stops between the zones and seven stops inclusive of the end stops Either a six stop or seven stop approach can work if they are used constantly The use of six stops employs the center tonal values the seven stop approach assumes the use of the limits of tonal potentials for Zones II and VIII We will use the six stop range for our calculations To find our N values we need to make another graph that plots develop ment times against light rendering capability from our testing On the hori zontal a
127. ure is increased by one stop Note that the effects of changing the print exposure will be most noticeable and controllable in the center of the zone scale Zones III through Zone VII Also because we want to ensure repeatability in our results the paper grade should remain a con ZONE PLACEMENT 41 stant In this case we used a grade 2 paper We could also use a 2 filter with Photo by Christopher Broughton multi contrast paper To summarize then you can use the following steps to ensure that the tones in your image will match the previsualized photograph 1 Previsualize the zone you wish to have appear in the final print 2 Meter the area of the scene that you wish to have in the final print The reflective light meter reading will give an exposure to make Zone V ZONE PLACEMENT GIVES YOU 3 Count the number of zones between the previsualized zone and Zone V 4 If the zone previsualized is lower than Zone V e g Zone II III or COMPROL GE ONEONE TONAL ARES IV then stop down the aperture or increase the shutter speed one stop IN THE SCENE for each zone you wish to change If the zone previsualized is higher e g Zone VI VII VIII or IX then open up the aperture or decrease the shutter speed one stop for each zone you wish to change 5 Develop the film normally Zone placement gives you control of only one tonal area in the scene As you move the chosen tonal area up or down the rest of the tones in the image will mo
128. ure will be the frame where your white card value is approximately 245 with no exposure adjustment If you organize the shooting and corresponding white point data in order of exposure from most exposure to least exposure you can see which expo sure s white point is closest to 245 That is the exposure closest to the ISO set in the meter The optimal ISO setting EI is the number of stops 1 4 or 1 2 away from the camera s set ISO If the EI is below the meter setting you must reduce your exposure Conversely if the EI is greater than the meter set ting you must increase the exposure Obviously this is only viable if the cam era is used in manual mode using the light meter used for testing It is also important to record the light meter readings for the white card and the tex tured white area of the test scene When determining the highest amount of overexposure that your camera will allow while still recording detail in white highlight areas start by setting the new EI as your ISO for metering and view successively overexposed frames To avoid clipping you can use your image editing software to adjust the exposure setting the white card to a value of about 242 With this ac complished magnify and view the white textured material and look for the loss of detail color shifts blooming and color fringing You can observe the highest amount of overexposure that your camera will allow without loss of detail
129. use of eight stops of neutral density filtration and a small aperture the exposure time calculation was long When including the failure of reciprocity the exposure time was five minutes The film had to be under developed to control the highlight contrast Photo by Glenn Rand 90 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY CHAPTER NINE ADVANCED PRINTING TECHNIQUES IF WE CHANGE THE DEVELOPMENT WE STILL CAN REACH COMPLETION AND MAINTAIN OUR BLACK DENSITY Facing page Photo by Glenn Rand It is as Ansel Adams said The negative is the score the print is the per formance The advanced film and printing techniques presented in this chap ter will allow you to accent ideas in your photographs and to strengthen what you communicate to your audience GLOBAL CONTROLS Control can be used to affect the overall image or in local situations Of the overall or global controls the selection of the correct contrast is the first and most important consideration Too often we select a high contrast paper or filter because the image appears crisper even though it loses both highlight and shadow details To avoid this you should start by using a lower grade paper or lower number filter Once you have made your print with the lower contrast you can make adjustments by adding more contrast to the print DEVELOPMENT CONTROL We often think of graded paper as offering no flexibility in contrast Though
130. used This darkened the handprints in relation to the wall Photo by Glenn Rand also helps in haze penetration On the downside it greatly reduces shadow exposure The yellow filter is often used to increase the contrast between the blue sky and the clouds While yellow darkens the sky it tends to lighten light green or May leaves Because the light in open shade is very blue the yellow fil ter will also increase the difference between lightness of areas in the sun and in shadow Orange filters also darken blue water and blue sky These increases in con trast and darkening of shadows are stronger than those produced with a yel low filter but weaker than those created with a red filter This filter has the most effect for blue and blue green absorption The green filter is often used to increase the tonality of people with lighter skin in order to enhance shape or make the subject look healthier Green or yellow green can also be used to comparatively lighten leaves while darken ing both earth tones and the clear sky There are also some filters that are partially colored and partially clear These are gradient filters and they exhibit a density that gradually changes to clear allowing photographers to alter the contrast in only a portion of the scene These balance large areas of different exposures A neutral density or red gradient could be used to darken the sky while leaving other portions of the scene unaffected However the g
131. ve proportionally in the same direction ALTERNATIVE METERING METHODS There are three metering methods that are based on zone placement These are commonly used methods that require no change beyond the metering exposure process While these methods affect exposure for digital and film photography differently they can help you achieve good exposure 42 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY THIS EXPOSURE METHOD COMMONLY USES ZONE III AS THE METERING POINT FOR PROPER EXPOSURE Photo by Christopher Broughton Dark Tone Metering Perhaps the most useful and nontechnical approach to film exposure based on the Zone System is dark tone metering This ex posure method commonly uses Zone III as the metering point for proper exposure It is a specific application of zone placement Because image sen sors do not tolerate overexposure dark tone metering is a very poor method for digital photography Many photographers have heard the phrase Expose for the shadows and develop for the highlights Shadow detail is less affected by development than highlights which are very susceptible to and controlled by changes in development Therefore you need to expose for the shadow detail or it will not be in the negative You determine what part of the scene you want to be Zone III shadow de tail and take a reflective light meter reading in that tonal area Then stop down two stops from the meter reading for a correct exposu
132. verexposed and the darkest tone above the noise level that the sensor can capture Though film can be developed to alter the range of Photo by Glenn Rand Photo by Glenn Rand light that can be effectively captured digital sensors have a maximum fixed dynamic range We can work on the values defined within the dynamic range but cannot expand the range when processing the file in the computer A misconception by some using digital photography is that if you work in 16 bits per channel raw mode you have a sixteen stop dynamic range As and analogy if we consider a meterstick a ruler one meter long as the dynamic range we can divide it into 100 centimeters or into 39 37 inches Regardless THE ZONE SYSTEM FOR DIGITAL PHOTOGRAPHY 109 meam Tew T a the dynamic range does not change only the number of divisions changes The same is true of the way a sensor captures light If the sensor captures light at twelve stops in dynamic range then that is the length of our me terstick If we divide the dynamic range into 8 bit channels there will be 256 divisions between maximum white and black However if we use 16 bit chan nels we are dividing the white to black range into 65 536 parts While it is better for post capture use to have the file in 16 bit channels using this set ting does not provide a greater dynamic range capture than the same sensor providing 8 bits per channel Another issue that must be addr
133. very easy to keep your processing wet time exactly the same and vary development with different developer dilutions With all concentrated developers T Max HC110 etc you can do this VISUALIZING THE SYSTEM 51 THOUGH THE PAPER FUNCTIONS AS A CONSTANT IN NATURE THE LIGHT IS BEYOND OUR CONTROL Facing page Photo by Glenn Rand CHAPTER SIX DEVELOPMENT In looking at the technical side of the Zone System we see three distinct parts of the process of moving from the scene to the print that we previsual ized These are the print the light in the scene and the negative s develop ment If the process were an algebraic formula one part would be a constant one part would be an independent variable and one part would be a de pendent variable Let us define how these might function in an abstract mathematical struc ture to simplify and show how the Zone System works In our algebraic for mula the constant is the goal and the dependent variable controls the effects of the independent variable If we have the equation Print Light x Development we can see how simple the Zone System is at its base In this equation the print is the constant The paper has a limited exposure range Though the paper functions as a constant in nature the light is beyond our control i e it is an independent variable Since the film s development changes its slope and thus its ability to capture varying dynamic ranges this contro
134. x 100 developed in D 76 1 1 at 70 F Example 1 The image was captured before dawn I previsualized the clouds in this scene as Zone VI and the dark rocks as Zone II This meant that the tonal separa tion in the scene was four zones and the metered light had a six stop range Even though the light was low in intensity and diffuse it required under development because the tonal separation was larger than the zone spread Here s how the situation was handled l Determine the light There was a four stop range Zone VI Zone II in Photo by Glenn Rand the previsualized image The metered light read f 2 to f 16 or six stops 2 Calculate the development Determined Zone Difference Metered Zones Development 4 6 2 Therefore the development was N 2 3 Adjust the ISO ISO 64 was entered into the light meter 4 Expose for the shadow detail I took a meter reading at the area I wanted to represent as Zone III in the print 5 Set the exposure I stopped down two stops from the exposure reading obtained in step 4 and made the exposure Processing the film upon return to the darkroom I used D 76 1 1 for 7 2 minutes at 70 F This exposure and processing allowed me to adjust the tonalities of the scene to produce a density range in the negative with only four stops between the previsualized tonal areas of the scene Though the bright areas of the sky moved to Zone X the shadow detail was maintained 74
135. xis evenly space out developing times to include more time variation on each end than you used in your testing For example if your longest de veloping time was twelve minutes and your shortest was six minutes you should include development WITH THE INFORMATION GENERATED FROM EACH CURVE WE NOW HAVE A SET OF DEVELOPMENT TIMES This graph will allow you to adjust your development to the scenic light the subject brightness range SBR Seeing how the graph s line for a point representing light is dif ferent than normal light and translating that to the time scale gives you the development time for the measured light times from five to fourteen minutes On the verti cal axis arrange from bottom to top the stops of light SBR from one stop more than the greatest number of stops gained in the testing to one stop less than the least number of stops gained in testing By arranging the graph this way we have created Li Lt r a listing of development times given in terms of N values In our example 6 min 8 stops 7 min 60 FILM amp DIGITAL TECHNIQUES FOR ZONE SYSTEM PHOTOGRAPHY 5 F a0 il it Ey H Deak pore nit Tira ma Photo by Glenn Rand IN ADAPTING THE FILM FOR DIFFERENT SBRS WE NEED TO OVERDEVELOP OR UNDERDEVELOP 6 5 stops 8 min 5 5 stops 10 min 4 5 stops and 12 min 3 7 stops When we draw the graph we can find the development times for the N val ues by seeing where the

Download Pdf Manuals

Related Search

Related Contents

BRB2617.5 Built-in combi frost free fridge-freezer  Origin Storage 120GB 5400RPM Notebook Drive  iOptron SmartStar MiniTower Pro User's Manual  VR602c - Videoswitch  Intellinet 710459 rack accessory  Numark Industries SA3000 Stereo Amplifier User Manual  I -MANUALE DI ISTRUZIONI PER SALDATRICE AD ARCO pag. 2    los proyectos hacen los objetos eternos, las modas los  

Copyright © All rights reserved. Failed to retrieve file