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1. Figure 1 26 Open the second test shot Varis_091120_0636 dng Canon EOS SO Mark I White Balanga 6100 12 JULIOL Figure 1 27 Create the second table and you will have a complete dual temperature set waiting to be saved At this point all you need to do 15 select File gt Export your camera name profile and give the file a meaningful name Figure 1 28 The DNG Profile Editor finds the correct location for the profiles so that they can be used in ACR or Lightroom DNG Profile Editor 7l Edit View Options 6 Open DNG Image Close DNG Image Close All DNG Images Open Recipe Save Recipe Save Recipe As Revert Recipe Export Canon EOS 5D Mark Il profile f Figure 1 28 Save the complete camera proXe from the File menu Note that to create the profile you opened two test images one for 6500 K and one for 2850 K and you built individual tables for each The RAW processing engine that Adobe uses interpolates color values between and beyond these common color temperatures to arrive at a correct interpretation of color in a wide range of different lighting conditions Creating a Custom Lighting Profile There is a third choice for building the color tables for a camera profile both tables If you select both tables the DNG Profile Editor will build both the 6500 and the 2850 table from whatever single image is open This is less than ideal for a general purpose table but it can be useful f2. Below Original Existing Files Ask what to do Y File Naming Template CustomName 9 Custom Text X Rite Passport Start Number 1 Lowercase 5 Example X Rite Passport tif Extensions V File Settings Format TIFF Compression None B Color Space sRGB Bit Depth 8 bits component 2 Add Remove F Plug in Manager Cancel gt Figure 1 32 The X Rite ColorChecker plug in is accessed through the Export dialog in Lightroom CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E 8 N 9 MOTAMMOM 21 211114172 19711211 215 79 E OO Oe _Export Export 2 selected photos to X Rite Presets 5 Preset Settings gt Lightroom Presets Y ColorChecker Passport gt Photomatix X Rite Presets DNG Profile Name X Rite_Dual 5Dmkill ColorChecker Passport The profile generated will only be selectable for images created with the same camera model Enter v User Presets a meaningful name that describes the shooting conditions this profile represents for example this Book Tiffs may include lighting conditions or lens choice Y Dual Huminant DNG Profile Instructions DNG Camera profiles can also be made with two illuminants For example Adobe DNG profiles include color tables for a very warm tungsten light source and a cooler daylight This type of profile is a Dual Illuminant DNG Profile It can be used with
3. and not an end in itself Putting Color Management in Context Color management is a relatively new discipline that is still evolving The goal of color management is to control color appearance in various input and output devices so we can achieve better agreement between the different renderings of the same image viewed in different media Notice that we are specifically not talking about color matching Real color matching is currently impossible and some level of difference has to be tolerated There is considerable disagreement about what differences are tolerable under what conditions so talking about color management in absolutes is difficult Control over color is highly desirable however whether or not we agree on how that control is applied Color management starts by attempting to define color in an unambiguous way Not too long ago a group of manufacturers in the graphics industry got together and developed the ICC profile as the foundation for a digital color definition An ICC profile references the color appearance of a particular device camera monitor printer to a numerical representation that is independent of any specific device This numerical representation is currently CIE L a b CIELAB essentially the same as Lab in Photoshop Profiles are generated by capturing the color rendering of specific devices and mapping the results to the numbers required to generate colors on that device As an example your monitor uses
4. are obscured by the printing linescreen If you are concerned with the best possible quality then you probably will pre fer to record the camera s RAW signal and process this data using your computer soft ware ina RAW file workflow Doing so complicates the process slightly by adding an additional post processing step to your photography workflow The main advantage to a RAW file workflow is that you can postpone final decisions on color rendering tone and contrast until after the shoot when you have fewer distractions and you can concentrate on basic photo elements such as lighting composition and exposure You also gain a considerable amount of control over color rendering tone and contrast The disadvantage is that you have to take extra time after the shoot to process your RAW files into a useable format Your Monitor and Calibrator After pixels are captured and assembled into images those images need to be viewed and interpreted Every image creation system must include a monitor to view the cap tured images A good monitor is an absolute necessity for any serious photographer However a good hardware calibrator is even more important Figure 1 3 You ll need to purchase a calibrator with the necessary software and use it regularly to keep your display in good working order Even a mediocre display can be serviceable if it is prop erly calibrated but an expensive display is almost useless if it lies to you Calibrate your
5. data in the Red channel simply by looking at the histogram display on the camera Working with Your Calibration Although a full exploration of Adobe Camera Raw or Lightroom is beyond the scope of this book I can offer the following general breakdown for RAW file processing using Adobe products Ideally you should shoot a gray card in the same lighting as the bulk of your subject matter Have the subject hold the ColorChecker or a gray card For the test shown in Figure 1 40 I stood in for the subject and had an assistant shoot for the gray card The remaining shots were taken of the real subject and this shot was used to white balance only Most often this can be a simple test shot done at the beginning of a shoot Figure 1 40 Shoot a gray card in the same lighting as the bulk of your shots When you are ready to process the shots simply use the White Balance tool on the gray card in the first shot adjust any other sliders you like and apply the settings to the rest of the images After applying White Balance select all the images and then in Lightroom click the Sync button located in the lower right corner of the interface and click OK in the dialog box that opens Figure 1 41 CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E 8 MOTAMMOM 21 21111172 19711211 215 79 E Figure 1 41 Sync the Xes in Lightroom Similarly in ACR click the Synchronize button located in the upper left cor
6. plished using software in an automated fashion Remember that color is not nearly as critical as value or tone Ideal color is fairly subjective and the photographer will be compelled to interpret and adjust for creative effect after the image is captured However it makes sense to start from a neutral unbiased point and so the color cali bration step should be included just don t lose sleep worrying about how accurate your color is Testing Procedure Overview The testing procedure breaks down into the following items Shoot an X Rite ColorChecker 24 Patch Classic target in shade and tungsten lighting Measure a mid gray reference of 18 percent and open to determine base exposure Bracket around the expected normal exposure two stops under and two stops over Increment exposures by V3 stop using shutter speed if possible Change the E I reference on a card in the shot to reflect the change for expo sure 100 80 64 50 for V3 exp Import files into Lightroom or ACR with Zero slider settings Evaluate the exposure sequence for the ideal exposure Use this information to enter an exposure compensation factor in the camera or as an E I setting in a hand held light meter CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E N w N LXALNOO NI LNAWAOVNVW 10 102 NILLAd E Open the ideal exposures from the shade and tungsten lighting shots in the color calibration software X R
7. the open catalog with the date so I know ata glance which catalog I m working with Inside the year image folder are the individual jobs folders all labeled with the date year month day and a descriptive name Inside the job folder is a RAW folder that contains the RAW captures as well as a WIP folder that contains work in progress PSD files When images are finished for delivery or printing I make a Finals folder for them Inside the RAW folder the images files are named with my name followed by the date followed by the camera s unique file identifier number I download images from shooting sessions directly into this structure Once that is done and the images are renamed I am finally ready to import the files into Lightroom This way the folder structure of the image archive is exactly reflected inside Lightroom so I can always find images from specific shooting dates without having to search filter or otherwise perform any catalog gymnastics The folder structure is clearly visible in the Folders pane of Lightroom s Library module Figure 1 6 foe 2009 leat Adobe Photoshop Lightroom Library Library ate Figure 1 6 The Lightroom Library module shows the hard drive folder structure at the left in the Folders pane Lightroom has become my software tool of choice for organizing and processing my growing image collection Just about every imaging tas
8. 01127 0636 dng Canes 05 50 Mark White Balance 6100 12 L Ogee an erage of ar Z the maui to positon tq four collared Girl the of the Poer cone porches of cha chart Tha cf pha giamh doeld po oF the patch 3 Seige mhich aipin you wish crests bom the mean B K aniy E 4 Cici he button below Create Coler Tabie Figure 1 23 Open a test shot and click on the Chart tab Follow the instructions and position the four colored circles dots over their respective patches on the target You can zoom in on the chart image to make it easier to position the dots in the middle of the patches Figure 1 24 GretagMacbeth ColorChecker Color Rendition Chart bi Figure 1 24 You may need to zoom in to position the colored dots accurately Select 6500 K only from the drop down to identify the color temperature of the table you will create Click the Create Color Table button and you will be brought back to the Color Tables tab with all the patch colors mapped onto the Color Wheel The table is created Figure 1 25 If the test was shot correctly and you chose the appropriate exposure
9. 091121_DeathValley Varis_091121_9337 dng u O 091220 Chrysler Varis_091121_9338 dng Lj 2009 4 nems 719 56 GB available O Lightroom Settings Lightroom_jdentity 2009 p5d gt LR 2009 Previews irdata 3 LR 2009 ircat Figure 1 5 Dual external hard drives set up as Archive and Archive_ Backup I keep all my images on an external hard drive this is my image archive that I duplicate onto a second hard drive This backup drive gets updated every day or when ever I have made any changes to my images or my image catalog Once a week this duplicate is moved off site and a third hard drive is brought in and updated to the cur rent state of the image archive this now becomes my new backup and is maintained every day in the same fashion After a week of activity the third drive goes off site and the second drive is brought back and updated The two backup drives are continuously cycling on and off site so I always have a disaster insurance copy in the event of a fire flood meteor strike or other such event that would render both my archive and backup unuseable The root level of the archive contains two folders one for the images and one for the Lightroom catalogs Images and catalogs are organized by year I make a new catalog every year to correspond to the image folder for that year Inside the year catalog folder is the Lightroom catalog file previews file settings folder and the identity plate file that I use to label
10. 13 Use the General Zeroed develop preset to get everything set up with no adjustments Make sure you are using the Camera Neutral calibration preset to get as unbiased a rendering as possible Figure 1 14 Once your sequence is imported you can survey the images for a quick fix on the best exposure Figure 1 15 Before you start making serious evaluations do a white balance click on the light gray patch second from the left with the White Balance tool the Eyedropper in the Basic panel of the Develop module The images will appear very flat and this can bias your judgment so it is best to evaluate the images using numerical readings off the mid gray patch a E E E FE 5 MM all all e Figure 1 13 Set the Develop Settings to General Zeroed and import the test images into Lightroom nas tamama hayra A VA 3 i i Develop Figure 1 14 Inthe Develop module select Camera Neutral in the Camera Calibration pane Library 0 5 1 i i 1 F an e elt Em n a HTA f 1 el a Figure 1 15 Evaluate the exposures for the best overall exposure and zoom into the most likely candidates Look for the exposure that gives you a reading close to 51 percent and very importantly without having the white patch go over 90 percent Move the cursor into the image and look at the numbers that show up right under the histogram display as shown in Figure 1 16 In
11. This is pretty much like exposing to the right of the histogram but with greater precision The only drawback is that the previews on the camera LCD might seem a little bright Adobe Camera Raw is the only RAW processing software I m aware of that allows for true zero or linear defaults in all its settings so this calibration strategy won t work with your camera software or something like Phase One s Capture One software Exposing to the Right You might have heard that it s a good idea to expose to the right of the histogram Experts often recommend doing so when you evaluate the exposure based on the histogram display on the LCD on the back of the camera see the accompanying graphic The idea is to open the exposure enough that the main peak in the histogram is right of center but not slammed against the right edge thereby placing the captured data where most of the useable bits are The idea is good in theory but bad in practice because the histogram cannot tell you where you are placing your tones with any precision and it can t tell whether the histogram is appropri ate for the subject What picture goes with this histogram The camera s histogram is only a general indication of the distribution of values in the camera generated JPEG It is usually a composite of all three channels The RAW data has a much wider distribution of tones that will vary in each channel 50 you may not know if you are clipping important
12. display every two weeks to be on the safe side Notes Many hardware calibration devices are on the market Some popular systems are the i1Dis play X Rite the ColorEyes Display Pro Integrated Color and the 83 20101 Display Color Solutions o 4 b s b art b en s a r sosse toa bevea ete foun w Figure 1 3 Monitor calibration CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E MOTAMAOM 21 211111972 17112211 215798 ON I highly recommend that you choose a simple gray desktop color and select a gray interface option for the overall color scheme for your computer The idea is to eliminate as many color distractions as possible for the environment in which you will be making color decisions If the background behind your images is bright blue you will tend to see everything as warmer than it is because of the color contrast with the blue background You probably will have a tendency to make your colors too cool as a result A neutral gray background is the safest choice because it will not bias your judgment one way or another Basic Digital Capture Workflow You need to develop consistent procedures for capturing saving and working with your images Each picture taking situation will demand a slightly different series of steps depending on your specific hardware software and working preferences At the most basic level you will be Capturing images Downloading image
13. file and you re done Figure 1 31 AO ColorChecker Passport COLOR CReEcCkeR PASSPORT Save As x rite_dual 5D Mark Il dcp 3 Dual Illuminant DNG Where C CameraProfiles Cancel Save he Instructions A Dual Illuminant DNG profile is a single DNG profile representing two lighting conditions This profile can be applied to images taken in a wider variety of lighting conditions The two images used to build a Dual Illuminant DNG profile must be taken with the same camera 1 Drag two DNG images into the image pane ColorChecker Passport will attempt to automatically detect the ColorChecker in the images 2 If auto detection fails click on the comers of the ColorChecker in the image to manually place the crop marks Zoom in if necessary 3 Click the Create Profile button Give the profile a name and click Save The profile will be saved to the specified location For more information click Figure 1 31 Once you drag the test images in you can create and save a camera prole e o Export Export 2 selected photos to Y Hard Drive CD DVD Preset Facebook Lightroom Presets Flickr gt Photomatix LR2 GMail X Ri Specific folder 8 X Rite Presets Photobucket ColorChecker Passport Photomatix Volumes Archive 4 Pictures posureBook Chapter2_Materials Choose Y User Presets SmugMug Put in Subfolder Exported DNG Files Book Tiffs C Add to This Catalog Add to Stack
14. gt Convert Photo to DNG from the menu bar The DNG Profile Editor only works with DNG files so you will need to convert all the good exposure shots before opening them into the software ACR requires that you save the files as new DNGs Launch the DNG Profile Editor application and you will be presented with a simple color editor the first tab at the top of the interface and the helpful instruction Tip Start by opening a DNG Image from the File menu Figure 1 22 Open the shot from the open shade test and then click the Chart tab Figure 1 23 The image should open with the white balance you set in Lightroom or ACR If for some reason it doesn t simply click on the light gray patch to reestablish a white balance Four small colored dots will appear in the image they are referred to as colored circles in the on screen instructions CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E Le N w MOTAMMOM 4AN LdVO 19711211 215 79 E DNG Profile Editor File Edit View Options OAC Untitled Recipe l Color Tables Tone Curve Color Matrices Options Chart Base Profile None Ky Color Table 6500 K B R B a G b Hue Saturation Lightness Tip Start by opening a DNG image from the File menu Figure 1 22 The DNG Prole Editor opens with the Color Tables tab active DNG Profile Editor File Edit View Opt Cale Tabled Tava Cura Clo Minded ea Chut Varin
15. in ACR to apply the profile follow these steps 1 Open the images in ACR 2 Select them click on the Camera Calibration tab and select the profile you saved earlier from the Camera Profile pop up Figure 1 36 5 1 Camara Aam 6 0 Carn Di 50 Mark m Mio Sees eel lolol Cama DH HO Mark a ELS Kabe A AEF Tet Gen Gn Figure1 36 Apply a camera proMe in ACR 3 To save a new Camera Raw Default apply the profile and then go to the Basic pane 4 Set the white balance to As Shot and set any additional adjustments you prefer 5 Select Save New Camera Raw Default from the settings drop down FEE 1 37 A Camera Raw 6 0 Canon EOS 5D Mark Il Wo oc 74 5 1 1006 GO 100 24 7048 mm va 5 9 R 6 image Settings Camera Raw Defaults Previous Conversion Custom Settings Preset Settings Apply Preset Apply Snapshot Clear Imported Settings Export Settings to XMP Update ONG Previews Load Settings Save Settings Save New Camera Raw Defaults Reset Camera Raw Defaults il 3 F 1 Recovery o Figure 1 37 Save anew Camera RAW default in ACR Editing Camera Profiles for Better Skin Color One common issue with digital capture is that any red component in the skin color can be overemphasized and people often complain that the skin color turns out too red
16. my example the gray patch is closer to 51 at the ISO 64 exposure where it reads 53 percent however the white patch is 100 percent clipped The next exposure down would give me an ISO of 80 and here the gray patch is at 48 percent This one still doesn t quite work because the white patch is 93 percent Figure 1 17 So in the end Pm back to ISO 100 where the gray patch now reads 43 percent but the white is at a safe 85 percent Figure 1 18 Once you have found the ideal exposure you can calculate what kind of compensation you will need plus 4 to plus 1 stop are common It is also common for this compensation factor to be different depending on the color temperature of the light For my Canon 5DmkII the compensation for direct sun is 24 for open shade it is 0 no compensation and for tungsten it is 1 Most of the time you can enter this compensation into your camera settings if you rely on your in camera meter I will typically enter an average exposure compensation across all three lighting types for my in camera meter settings and just leave it there Another thing to consider is that you can often recover up to one stop of highlight detail with out suffering image degradation but using Fill Light or something similar to recover shadow detail will result in extra noise So if you are going to err err on the side of over exposure In my case for this camera I would use an exposure compensation in camera of 24 even though that
17. of red green and CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E N STAXId ANV SdIHO E w blue for each pixel We therefore think of these pixels as being in three channels Red Green and Blue simultaneously so that the complete image is recorded as three different black and white B W images that form the full color version This concept will be important when we get to color correction The number and density of receptor sites on the chip determine the resolution of detail This pixel count is given as either dimensions such as 4992x3228 or as a total such as 16 megapixels where mega means million totals are usually simpli fied to the nearest decimal Therefore an 8 megapixel chip has less resolution than a 12 megapixel chip Professional quality people photography can be done with cameras delivering 8 megapixels or more of resolution Pixel count can be manipulated after the fact through mathematical calculations that interpolate new pixels from existing ones but the amount of image detail can never exceed the original resolution of the chip That being said there is no reason for you to obsess over the number of pixels available as a standard of quality Movie posters have been made from images with fewer than 6 megapixels and the quality of those pixels in terms of lack of noise and fidelity of color information is more important than the quantity used for photograph ing people Bayer Pattern Chip
18. 5 nt mareg ce a a pi Hg NOILVUGITVO ONV 230 112110 5521590 ONIOVWI 1711292101 E Digital Imaging Basics Workflow and Calibration Every journey begins with the first step Unfortunately for many the temptation to skip the first step is enhanced by the belief that they already know how to take pictures After all we ve been snapping photos since we were kids haven t we Modern cameras do everything automatically don t they For consistent success you need to predict the outcome of the image capture with certainty and for professional results you can t rely on the display on the back of the camera Before you begin you need to learn how digital photography works and develop an image capture workflow then you need to test and calibrate your equipment Only then can you take the first tentative steps to digital photo mastery Chapter Contents Chips and Pixels Basic Digital Capture Workflow Calibrating for Digital Capture Color Management in Context Chips and Pixels All cameras function like human eyes Figure 1 1 In both a lens focuses light through a small hole iris onto a receptive surface retina film chip that translates the varying intensities and colors of the light into meaningful information The main distinguish ing feature between different cameras and the eye has to do with the receptive surface The eye s retina 15 a receptive surface comprising two different str
19. 9711211 215 979 E A spot meter can read directly from the mid gray patch third from the right on the bottom of the ColorChecker open up 4 stop to get the base exposure If you don t have a spot meter use an incident meter and take a reading from the subject position pointing the white dome at the main light source Figure 1 10 The ideal way to take exposure readings at least for the test is to use a hand held light meter A hand held meter is better than relying on the camera meter for a number of reasons If you have to use your in camera meter get yourself a large reference card like the Lastolite EZ Y Balance Figure 1 11 You can move in close enough to fill the frame with the large gray field Remember to open up stop from any reading off any 18 percent gray reference e a i 2 SERONIL 0 i i f Rendition Chart Figure 1 10 Point the incident meter dome at the light source Once you ve determined your starting exposure you will shoot additional exposures incrementing the f stop value by 14 f stop using the manual controls on your camera Shoot two stops on either side of the starting exposure and keep track of the exposures as you go along I find it convenient to indicate the exposure change on the target itself by writing on a paper attached to the target I write down the differ ence in exposure as a change in ISO In other words if I stop down one third from the ISO 100 rea
20. If you find this to be the case with your files even after you ve built a calibration you can tweak the red out in the DNG Profile Editor First you must arrange to shoot a test with a subject that exhibits the red skin defect in your digital captures Once you have tested and identified the ideal exposure open the DNG in the DNG Profile Editor application Build the tables as usual but before you save the camera profile zoom in on the subject s face The same keyboard shortcuts you use in Photoshop apply Command space or Ctrl space See Figure 1 38 Now find an area on the face that has that overly pink look to it As you scroll over the image look at how the color values as displayed in the region above the color patches to the right change Good skin color will have Lab values with the a and b numbers equal or the b value slightly higher In the example here a 17 and b 9 This area is too red Click on the spot and a dot will appear in the Color Wheel where that color lives ONG Profile Editor File Edit View Untied Recipe _ 131 gi E tp 1 j s 17 G l b 1 1 N N E gt Figure 1 38 Zoom in and locate an area of red skin Now take the Hue slider and move it to the right toward yellow the last patch in the column of patches will show the before and after of the color you are now editing Figure 1 43 You may want to reduce the sa
21. a certain set of RGB numbers to generate a color that can be defined as a specific shade of red in Lab When you want to display that shade of red as defined in Lab on another monitor you will likely need a differ ent set of RGB numbers If the other monitor has been profiled you can derive the new set of RGB numbers by running the Lab numbers through the profile for that monitor As such profiles allow for some method of translating colors for different devices by referencing into and out of Lab Profiles are also used for generic color editing environments called workspaces Adobe RGB Colormatch and sRGB are examples of standard RGB workspaces An RGB workspace is defined in a way that allows for easier color editing and one unique property of this is that neutral gray is always defined with equal values in red green and blue One of the common activities in color management is transforming color numbers from a capture device into workspace numbers for editing and then transforming those numbers into numbers appropriate for a printer or display device for viewing Most of the problems associated with color management concern the mismatch between color spaces with different gamuts Color gamut is the volume of colors defined in a given color space The real world represents a huge volume of possible colors Digital cameras are capable of encoding a somewhat smaller volume of colors The Adobe RGB workspace is smaller still and almost every o
22. a wide variety of light sources with very good results X Rite Dual Illuminant DNG profiles can be made with any two supported illuminants Instructions Select two images taken by the same camera and lens Each image must be taken under a different lighting condition Learn More 4 Add Remove Y Using a custom DNG profile y Plug in Manager Cancel Figure 1 33 Select the X Rite presets and the dialog changes to accommodate the creation and saving of camera proles The Lightroom plug in is particularly easy to use because you never have to leave Lightroom The plug in is invoked from the Export dialog select X Rite Presets from the Export To drop down menu Figure 1 32 The dialog changes specifically to accommodate saving DNG Profiles Figure 1 33 The resulting file is automatically saved to the correct location Both Calibration systems work well to provide customized camera profiles for your specific camera The X Rite software seems to generate slightly more saturated color is a bit easier to use and comes with the very handy target I personally prefer the less saturated results I get with Adobe s DNG Profile Editor and the Adobe soft ware offers the ability to manually tweak the color of the profile something I often find necessary with skin tone More on this later Using Camera Profiles As I mentioned earlier these profiles are not industry standard ICC International Color Consortium
23. be Camera Raw ACR as a system that works with the widest range of digital cameras There are other approaches but none of them currently offer as much control in a convenient and relatively inexpensive manner CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION MOTION AUN LAVO 19711211 215 79 E To calibrate your camera you must shoot a test The test shot will need to include some kind of standard target Figure 1 7 Figure 1 7 Sample test setup The most widely used target is the X Rite ColorChecker 24 Patch Classic Originally known as a Munsell chart this target has been in widespread use for at least 50 years in the motion picture and television industries You should be able to purchase one at any camera store An ideal test will include this target a human sub ject for real skin tone and some written reference for the exposure My test setup includes a black trap shown in the upper right This is a small cardboard box with a hole cut on the top the inside is lined with black velvet I like to include this for a real black reference because the black patch of the ColorChecker target is not very black My test target also includes a highlight reference some Styrofoam lens packing is in the lower right corner The curved form creates a soft ramp from near white into a clipped to white tone and allows you to see just how much detail is preserved in extreme highlights These ad
24. ding I write 125 24 160 1 stop 200 and so on The beginning of the sequence would go 100 80 64 50 Whatever you do don t base your exposure off the appearance of the LCD on the back of the camera See Figure 1 12 Not only do most viewing conditions prohibit accuracy but the LCD will only show you how the camera would generate a JPEG it can t show you what is in the RAW file Typically the histogram is only a composite histogram and even when you can display separate RGB histograms they are not accurate except as a rough approximation of the camera JPEG We are look ing for better than JPEG performance otherwise it s not worth shooting RAW In practice I find that relying on the LCD almost always causes you to underexpose the shot Of course with a lot of experience you can learn how overbright the image on the LCD needs to be to arrive at the correct exposure I personally prefer a more con trolled approach 2 i v Figure 1 11 The Lastolite EZYBalance MENU DISF Syd Figure 1 12 Donot be tempted to base your exposure decision on the built in LCD CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E y MOTAMMOM 21 21111172 19711211 215 979 E Importing Shots and Evaluating Exposure Now you have to evaluate the shots to determine the best exposure I will first look at how this is accomplished in Lightroom Import the image files into Lightroom Figure 1
25. dio Flash Lighting This is very similar in character to daylight but here you want to simulate your most common lighting Use the lighting you normally use for your sub jects use the same umbrellas or other light modifiers Don t do anything special just for the test If you use two lights make sure they are the same type or make You can skip any hair lights and just concentrate on your front lighting CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E w MOTAMMOM 21 21111172 19711211 215 79 E Fluorescent Lighting Shooting a test under fluorescent lighting is almost not worth the effort because each uncontrolled situation you encounter will be different Also fluorescent lighting is a really unbalanced spectrum with big gaps and spikes in the frequencies represented These situations almost always require some selective color correction in Photoshop after processing so the kind of calibration you achieve here will be of limited use If you frequently must shoot under a specific fluorescent light ing condition then you can test for that similar precautions against shadows and uneven illumination will apply Shooting to Bracket the Exposure Range The idea is to shoot a wide bracket around the expected best exposure to determine the actual best exposure Set your camera on manual and if possible change only its shutter speed to shoot the bracket Note Asyoumay remember back in the days of film we we
26. ditions are not critical for calibration purposes but they help to visualize the dynamic range of the capture in highlights and shadows Notes The skin color patch on the ColorChecker target is intended to represent average Caucasian skin Real skin comes in all different colors and it is practically impossible to represent every kind of skin Try to have some real skin that you feel is representative of your cultural average in your shots but gt don t obsess over it A real person in the test shot provides a visual reference to balance the technical nature of the target The testing procedure involves a series of steps which are summarized here 1 Establish lighting that mimics the conditions for 6500 K and 2850 K open shade and tungsten lights indoors 2 Shoot a range of exposures to determine your camera E I exposure index ISO or ASA rating 3 Import RAW files into Lightroom or ACR and white balance to the light gray patch 4 View the series of exposures in Lightroom or ACR and apply Zero slider settings 5 Identify the best exposure by comparing the exposures and reading numbers from the mid gray patch 6 Convert the best exposures to DNG 7 Open the two DNGs representing 6500 K and 2850 K color temperatures into Adobe s DNG Profile Editor or X Rite s ColorChecker Passport software and build camera profiles 8 Save your settings and create a new camera default setting for your ca
27. e it is very easy to use Launch the ColorChecker Passport application and you will see a wizard interface with instructions that walk you through the process Figure 1 30 8 XU 8 Fa 4 8 f K J 1 ig E ie m EEE HE LL Y T YNO Figure 1 29 The X Rite ColorChecker Passport target AOO ColorChecker Passport e COLOR Checker Dual Illuminant DNG gt Instructions A Dual llluminant DNG profile is a single DNG profile representing two lighting conditions This profile can be applied to images taken in a wider variety of lighting conditions The two images used to build a Dual Illuminant DNG profile must be taken with the same camera 1 Drag two DNG images into the image pane ColorChecker Passport will attempt to automatically detect the ColorChecker in the images 2 If auto detection fails click on the Drag and drop DNG images here comers of the ColorChecker in the image to manually place the crop marks Zoom in if necessary 3 Click the Create Profile button Give the profile a name and click Save The profile will be saved to the specified location For more information click here Figure 1 30 The ColorChecker Passport software provides on screen instructions Drag two different test shots preferably under shade and tungsten light into the image window The software will automatically locate the patches for each shot Then simply click the Create Profile button name the resulting
28. e the camera s color to a known target Adobe s processing software offers this capability though sliders in the Calibrate tab in ACR Lightroom offers the same capability on the Camera Calibration panel There is also a stand alone application DNG Profile Editor from Adobe in public beta at the time of this writing that simplifies the process DNG Profile Editor DNG Profile Editor is an application designed to modify the lookup tables that Adobe software uses to convert the raw data from the digital camera into a standard color workspace Every camera supported by Adobe Camera Raw or Lightroom has a lookup table associated with it to enable the raw processor to de mosaic or render color from the brightness data recorded under the red green or blue pixel sites on the chip The DNG Profile Editor uses various controls to manipulate the color result gen erated by the lookup table and regenerate the table and it has a straightforward cali bration process that utilizes the X Rite ColorChecker 24 Patch Classic The software will do an automatic analysis of an image capture of the target and generate a table that can be saved and used by Lightroom or ACR For our purposes I will use the tar get analysis function to build an idealized color calibration First select the ideal exposures from your test shots under the different color temperatures and convert the files into DNG format In Lightroom go to the Library module and select Library
29. files to a computer Adjusting the files cropping color correcting retouching Delivering images printing uploading saving Backing up files saving and storing The basic steps can change slightly depending on whether you are shooting RAW or JPEG tethered to a computer or to memory cards archiving original RAW data or converting to DNG format Many of the repetitive tasks can be automated in certain software or by using scripts Look for more details on workflow automation on the ww varis com skinbook website Note DNG Digital Negative is an open published RAW file format developed by Adobe to address the need for a standard format for digital camera data Currently most camera manufacturers use proprietary file formats unique to their particular cameras This is equivalent to Nikon cameras using only Nikon film which would be an unacceptable situation with the photographer at the mercy of the manufacturer to support his images A big push is underway in the industry to move toward an openly supported file format that will work with all cameras and most photographers see DNG as becoming that standard Most of the digital workflow occurs after the photo shoot because that is where you work with the captured digital data A professional workflow maintains a backup protocol from the beginning always maintaining duplicate copies of files at every step A typical progression of steps might look like this 1 After filling
30. ite or Adobe build a camera profile and then save it Set this calibration profile as a camera default in either Lightroom or ACR I encourage you to tweak your calibrations to suit your personal preferences You shouldn t necessarily accept the numerically accurate renderings of the color patches most of us don t sell pictures of ColorChecker targets Think about how you prefer your color More contrast More saturation Put these into your camera default settings so you don t have to tweak every file every time Remember you are calibrating a complete capture system that includes the lens You can usually count on lenses from the same manufacturer to have the same color bias but as soon as you switch to a different manufacturer a third party lens you will likely affect the subtle color bias and you ll need a different calibration For that reason I recommend staying with your camera manufacturer s lenses whenever possible Finally calibration is no substitute for creativity Feel free to break away from rigidly accurate color renderings to suit your creative needs or the needs of your cli ents Your calibration settings are only a starting point from which you are obligated to depart on a journey to your personal vision You should also save creative render ings as presets that you can call on for different purposes The calibration method outlined here should be considered a tool to allow you control over your photography
31. k short of retouching can be accomplished with it Its functions include making slideshows printing and making web galleries These functions are also expandable using third party plug ins Calibrating for Digital Capture Back in the old days serious photographers tested their equipment and film to estab lish the best working methods for their particular gear Ansel Adams developed the Zone System for his work with black and white film Commercial photographers shot tests through different color gels to determine the color bias of a particular emulsion as processed through their particular labs Testing was an ongoing process that pho tographers used to stay on top of their game Modern digital capture has opened up new possibilities for accuracy and color quality but the need for testing still exists We ll explore one approach to digital testing and calibration with a special emphasis on skin tones that I have used with my equipment and readily available software and hardware There are as many testing methods as there are cameras and software pack ages and the following is presented more to illustrate concepts than anything else I ve already mentioned monitor calibration this is a relatively straightforward process with a hardware colorimeter You must calibrate your monitor before doing anything else The next step is to calibrate your camera with your RAW processing software We will look at how to do this using Lightroom or Ado
32. mera Establishing Lighting You should shoot your test exposures under conditions as close as possible to 6500 K open shade and 2800 K regular incandescent or halogen lights color tempera tures two complete test sequences If you shoot mostly outside you ll also want to set up and test outdoors using direct sunlight as well To cover all your bases you might want to calibrate for other unusual lighting conditions Here are some consider ations for various lighting conditions Outdoor Daylight Try to set up in broad daylight under clear sky conditions Make sure that no shadows hit your target especially the ColorChecker Stay away from build ings as much as possible to minimize the effect of reflected light on your test if you set up near an orange colored wall it will affect the color Outdoor Open Shade Set up your test subject in open shade in an area that is illuminated by a broad expanse of blue sky Try not to set up under trees because light filtering through green leaves will pollute the color temperature Indoor Incandescent Lighting If possible use a single light positioned at a 45 degree angle to the target and about 10 feet away Make sure you re in a room with white or neutral colored walls Aim for as even illumination as possible again make sure no shadows hit the target You can use a higher ISO setting on the camera to bring the exposure within range but try not to go above an E I of 800 Stu
33. n problems because we often have to determine how we are going to compress the range of an image to fit the output You will often hear about bit depth in the same breath as dynamic range Bit depth refers to the number of steps between black and white that are encoded in a digital capture Higher bit depth captures have a finer density of steps and yield a smoother ramp from black to white however bit depth does not determine dynamic range It is certainly better to have higher bit depth with wider dynamic range but the two are not necessarily interdependent Lower dynamic range Higher dynamic range Higher bit depth Lighter More steps Darker Figure 1 2 Dynamic range and bit depth The RAW signal from the camera chip can be processed either in the camera firmware or later in software under user control There is some debate over the merits of both approaches Generally if you opt to have the camera do the processing you will be shooting JPEG files to the memory card or directly to a computer Note JPEG stands for Joint Photographic Experts Group the organization that developed the file format vie CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E STAXId ANV SdIHO Bw JPEG is a file format that was developed to reduce file size by using mathemati cal algorithms that simplify the pixel structure in the bitmap image This process is considered lossy because some image detail is lost d
34. nately mod ern software tools specifically designed with the photographer s needs in mind have become available I recommend using an integrated image processing and cataloging application such as Lightroom or Aperture My own preference is Lightroom so I will use it in the rest of this chapter Setting Up a Lightroom Catalog Lightroom is an image cataloging system that stores information about images in a separate catalog file It is beyond the scope of this book to provide full step by step instructions for using Lightroom but I will cover certain features that pertain to the various tasks under discussion in the following chapters Here we are concerned with getting started with an image catalog There are a number of different ways to use Lightroom to organize your images I prefer to have Lightroom mirror the file CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E MOTAIMMVOM 21 21111172 17112211 OISVA BO organization I have on my hard drives To accomplish this you need to begin with some organizational structure This is how I set up my hard drives Figure 1 5 Lj RAW 16 tems 470 CB avaiable E 090309 AnzaBorrego Varis 091121 9330 dng E 090423 Dubai Varis_ 091121 9331 dng E 090531 BlueNileCafe Varis_091121_9332 dng m 090902 Noelle Varis_091121_9333 dng E 090919 QueenOfCups Varis_091121 9334 dng DD 091010 GWW Spade Varis_091121 9335 dng E 091024 Aubre_Karim_Dance Varis_091121_9336 dng O
35. ner and click OK in the resulting dialog as shown in Figure 1 46 If you ve done a good calibration and you ve exposed properly you seldom have to do more than slight brightness and contrast adjustments to cook the image to taste ur 6 0 Canon EOS 50 Markii Figure 1 42 Synchronize the Nes in ACR If you do not have the opportunity to shoot a gray card you can select a default from the White Balance drop down in the Adjust tab ACR or the Basic pane Lightroom or you can accept the As Shot settings however a gray card takes all the guesswork out of the color and can save a lot of post production especially if you are working with a large volume of images Calibration Review The testing procedure consists of shooting the test target in a controlled manner cap turing a wide range of under normal and overexposures to see exactly the limits of the camera capturing capabilities Ideal exposure is determined with numeric precision so that the maximum amount of useable data is available for post capture manipula tion in software Under and overexposure limits are similarly determined so that you know how far you can go with a particular important tone in an image The goal is to be able to give the maximum useable exposure and thus ensure that you have the cleanest most noise free information in the captured image Once you have a good exposure of the test target color calibration is accom
36. or a specific lighting condition that might otherwise be problematic For instance you might shoot a test target under stadium lighting conditions to build a more accurate color table for the unusual sodium vapor lighting and get a better color rendering for the athletic teams jerseys Of course you would use this table to build a profile you would use only for this specific lighting condition more on using the profiles later X Rite ColorChecker Passport The X Rite color calibration system utilizes a special version of the ColorChecker target that comes in its own self enclosed carrying case and includes some extra warming cooling white balance patches for portraits and landscapes Figure 1 29 I prefer to use a full size Gretag Macbeth ColorChecker for the exposure tests but this little target is very convenient for quick color calibration shots Shoot the target in the lighting you want to test but simply aim for a good exposure no need to do more than a narrow bracket sequence just to make sure you have a good expo sure with which to work The ColorChecker Passport system comes as a stand alone application as well as a plug in for Lightroom that almost completely automates the CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E 9 N N MOTAMMOM 21 211114172 TVLIOId OISV4 creation of DNG camera profiles within Lightroom There are very good instructions with the software but it almost doesn t need any becaus
37. profiles but special Adobe formatted color lookup tables that can be used in ACR or Lightroom Both color calibration applications save the camera profiles in the appropriate place on the computer In Lightroom To use the profiles in Lightroom follow these steps 1 Select an image 2 Go to the Develop module and in the Camera Calibration pane select the pro file you saved earlier using the Profiles pop up menu Figure 1 34 You can save this camera profile along with any Develop setting preferences as a new Camera Default After applying the camera profile go to the Basic pane set your white balance to As Shot using the WB list box and then select Set Default Settings from the Develop menu Figure 1 35 You ll receive a warning and a confirmation of the camera model and serial number Click the Update to Current Settings button Now every time you import a RAW file from this camera it will appear with these settings and camera profile Develop Reape ra diliull wie by aed Carrere lr lar Lr Sled with the Aboi preparit niy ECG 10 hiri a ira aaa HARF Biria foie Pak Haat dih Fal dali Upin u Cem hn y Figure 1 35 Seta default setting in Lightroom CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E z w MOTAMMOM 21 211110172 19711211 215 79 E In Adobe Camera Raw Similarly
38. re told to bracket using f stops because shutter speeds were not as accurate Digital capture works differently The exposure is timed electronically not by a mechanical shutter in fact there is no curtain shutter just a mirror that has to move away Lens f stops will vary slightly from lens to lens and also just slightly across their range So the shutter speed is the most consistent way to bracket a continuous light source you only need to use f stops for flash Use the lowest default ISO setting for your camera A hand held light meter works best a spot meter would be ideal I use a combo meter that is capable of incident and spot reading in continuous as well as flash lighting Figure 1 8 The spot meter has the advantage of being able to measure the value of the mid gray patch third from the right in the bottom row of patches from the camera position Figure 1 9 SEKONIC Figure 1 8 Sekonic L 758DR Digital Master meter Figure 9 Spot meter readings are taken from the camera position The Mysterious K Factor The mid gray patch is calibrated to 18 percent reflectivity this is supposed to match the 50 percent luminosity that light meters are calibrated to but in fact it is off by roughly 1 3 to J stop Why this is so is unclear Many reference gray cards are referred to as 18 percent gray In the printing industry 18 percent reflectivity is considered halfway between the white of paper and
39. s The usual arrangement of red green and blue photoreceptors across a digital camera chip surface is called a Bayer pattern This regular pattern alternates green with red and blue so that there are twice as many green pixels as there are red or blue There are more green pixels because green holds 60 percent of the overall image luminosity lightness darkness in an RGB image The signals from adjacent pixels are averaged together using complex algorithms to determine the overall color and interpolate this into each pixel in the image Skin colors sit right between the red and green filter frequencies used in most chip designs and as it turns out calculating skin color correctly is difficult In digital photography skin color can end up being a little too red You ll learn how to compensate for this later The dynamic range of a captured scene is an important yardstick for quality Figure 1 2 This is the brightness range from dark to light that affects how much detail can be rendered in the darkest and lightest portions of the scene Dynamic range is often represented in f stops Digital cameras can often capture a range of 11 f stops from black to white whereas a paper print from a desktop inkjet printer might have at best a range of five f stops Regular offset lithography such as magazine print ing has even less dynamic range typically four f stops or even less This disparity between capture and output is at the heart of reproductio
40. s to make editing in Photoshop difficult After you set your workflow preferences the RGB numbers display will exhibit numbers that represent the chosen workspace in standard RGB from 0 to 255 In Adobe RGB you will look for the exposure that renders the medium gray patch clos est to 121 without pushing the white patch past 245 Figure 1 21 Once you identify the exposure you can calculate your exposure compensation much as in Lightroom Space Adobe REG OOOO OYO Size 5616 by 3744 21 0 MP 5 5 Sharpen For None ss Amount Low __ Open in Photoshop as Smart Objects Figure 1 20 The Workflow Options dialog in Adobe Camera Raw a ue E KF BiR perapti may AEN tins Coe Gem Figure 1 21 Evaluate the exposure in ACR using the RGB numbers just under the histogram Building a Camera Calibration RAW processing software is designed to interpolate color information from varying brightness of pixel sites that have a colored filter of red green or blue In essence there is no color in the RAW data color is inferred by measuring the brightness of pixel clusters The colored filters covering the tiny pixel sites are not perfect and manufacturing processes being what they are there is some variation from camera to camera even from the same manufacturer Some RAW processing software is set up to allow for a certain amount of adjustment to calibrat
41. space and not color management The odd color mismatch in a manufactured product can usually be tol erated however if you can t get good skin color you are in trouble CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E a w 9 LXALNOO NI LNAWAOVNVW 10 102 2111111 E For our purposes color management simply involves calibrating the monitor choosing an appropriate workspace and utilizing printer profiles at output You do not absolutely need anything more exotic than Adobe RGB as your workspace If you shoot RAW as you should then there really is no absolute need for a custom camera profile because the RAW data can be processed into a standard workspace in ACR The calibration steps we ve just gone through determine how your color is rendered into the workspace You can think of the workspace as the color definition that deter mines what the various RGB number values look like Once a file is tagged with a workspace definition or profile you can track the colors in the image through editing and finally into a print We will examine various color management issues as they come up throughout the rest of the book
42. the black of printing inks However actual scene luminance is a bit different than the brightness of printing ink on paper Light meters are calibrated to an ANSI standard of 12 3 per cent reflectivity which is a closer match to 50 percent luminosity or L 50 in Lab colorspace For some unknown reason reference cards in use for photography if they are calibrated at all choose 18 percent to represent medium gray This may come from Kodak who continues to manufacture and market an 18 percent gray card Kodak s cards are produced using print ing ink on an offset litho press and 18 percent gray actually refers to a printing specification Presumably this makes it easier to manufacture The bottom line is that the 18 percent Kodak gray card is a bit lighter than the 12 3 percent reflectivity that light meters are calibrated to and so if you expose at the reading you get from the Kodak card you will be underexposing by about f stop Ansel Adams was aware of this and made reference to a mysterious K factor in his book Camera and Lens His instructions there had you opening up by 12 stop from the reading off the card In general practice prefer the exposure precision afforded by adjusting exposure in 1 3 stop increments therefore to avoid overexposing only open 1 3 stop from readings taken off 18 percent gray cards CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E VI MOTAMMOM AUN LAIVO 1
43. there will be no problems If however the white patch is too bright clipped the program will throw up a warning and you ll have to pick another bracket or reshoot GWG Profile Editor File Edit View boris A Unidad Recipe leetan nim n Varii 091170_0635 dag Canon EOS 0 Mark il White Balance 6100 12 Figure 1 25 After creating the table you will receive a conXtmation and the Color Tables tab will open with the values fully populated CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E N N ui MOTAMMOM 21 211111752 19711211 215 79 E Next you will create the table for 28507 K Open the tungsten test shot This is more likely to be at 3000 K to 3400 K depending on the lights you actually used but it will be close enough for this purpose Once the tungsten test shot is open click the Chart tab select 2850 K only as the table to build and position the dots Figure 1 26 Again click the Create Color Table button and you ll be back at the Color Tables tab this time with the 2850 table created Figure 1 27 Varit DO110 6 36 dng Canon EOS SO Mark White Balance 6100 12 Inacruetniona L Open an imaga DC Daon haie cea ESA Waris_091202_9803 cdng Canon E S D Mark Ul White Balance 3000 6 J h which Geter Gabbe yo ease Tram ht Popup manu below 7 Create Color Table
44. turation of the color as well The beauty of editing the one problematic color in the Profile Editor is that it leaves more saturated versions of that particular hue alone so it won t damage lip color as much as it would if you were editing hues in Lightroom ACR or Photoshop When you are done editing save the camera profile as before and give it a descriptive name such as Camera Name Skin The profile can be used as a special purpose profile for those situations where you might have trouble with overly red skin color There are times when even this specialized profile cannot automatically render an ideal skin color so it won t eliminate post process color editing altogether but it will help when you are working up a large volume of images for approval before doing fine tuning on final selects CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E 8 w w MOTAMMOM 21 2111141752 19711211 215 79 E DAG Profile Editor File Ede View ptions Varia DOOR 22 F714 dng Camon EOS SD Mark Il White Balance Untitied Recipe Z R z a Coder Ta Figure 1 39 Edit color using the Hue and Saturation sliders When you calibrate this way you maintain the best possible quality and retain the most flexibility for processing your RAW files Establishing a calibration with Zero slider positions ensures that the RAW data is recorded at the highest signal level without encountering serious white point clipping
45. uctures rods and cones with three basic color sensitivities red green and blue Film is made of silver salt grains suspended in gelatin in three different layers to receive color Digital cam era chips contain photoreceptor sites on a silicon chip each photoreceptor site has one of three different colored filters to record light Figure 1 1 All cameras function like human eyes Digital cameras are similar to eyes in that the camera s chip translates the light into information electrical signals directly Much as the eye translates the light fall ing on the retina into nerve impulses electrical signals that travel to the brain for pro cessing the electrical signals from a digital camera require processing in a computer brain before they can be used to create photos The actual process is rather more complex but a few things are important to understand Most digital cameras capture images using chips with receptor sites that have red green and blue filters arranged in a regular pattern on the surface of the chip Light intensity is the only thing captured at a receptor site During the processing phase the color of light hitting a receptor is determined by calculating differences in intensities between adjacent sites that have red green or blue filters This process pro duces an RGB bitmap image A bitmap is a regular grid of square units of color These units are called pixels Color is determined by the relative values
46. uring the process Digital cam eras apply a conservative level of compression or size reduction and this is generally considered visually lossless This does not mean that there is no loss just that the loss is not apparent at first glance Even the best JPEG file does not carry the same amount of information or image detail as a noncompressed or unaltered version The main advantage to shooting JPEGs is that by compressing the file size you can fit many more images onto a memory card so you don t have to change cards as often Because the files are smaller they also write faster and enable faster shooting speeds This can be important for shooting wedding candids news sporting events and any other fast breaking action The disadvantage to shooting JPEGs is that you have to accept the camera s interpretation of color contrast etc and you limit the potential quality of the image You give up some flexibility and quality for speed and convenience JPEG Compression Artifacts JPEG compression works by simplifying adjacent tones similar tones are assigned the same value This can cause distinctive blocky artifacts and messy edges which are most notice able in extreme magnifications JPEG artifacts can become a problem when image files are sharpened for print output or scaled up from smaller sizes For most work destined for offset lithography magazines and newspapers JPEG artifacts don t pose a problem because they
47. utput device can repre sent a smaller volume than Adobe RGB Overall volume is not the only factor There are other mismatches Some possible colors in one workspace don t exist in another even if the overall volume in the second space is greater Imagine trying to fit a square peg in a round hole color spaces can be thought of as having 3D shapes based on different regions of colors The graphics industry has adopted various methods of translation or gamut mapping between the different color space shapes using ICC pro files in an attempt to mitigate the problems Most of the time photographers make a bigger problem out of this than is nec essary People photography is mostly concerned with the color of skin As it turns out skin color is easily defined in just about every color space with which we can work Conservative color spaces such as sRGB are perfectly adequate for people photogra phy and translating between sRGB or Adobe RGB and any type of output we need is not a problem Problems typically arise with attempts to match garment colors or other products that may be of primary interest to an advertising client Some products might contain colors that are outside the range of Adobe RGB but just inside CMYK for a magazine ad Sometimes the dyes and colorants used to manufacture these items do not reproduce accurately no matter how well the system is color managed Most of the time the solution involves color correction in the final output
48. would be overexposing in open shade lighting I only need to put the Recovery slider at 20 to get the white patch to read 89 percent Figure 1 19 CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION E 9 78 215 17112211 211114172 21 0 1 21 11 0 Develop Figure 1 17 The mid gray patch is still close but the white patch goes past 90 percent Develop Figure 1 19 Highlight detail can be recovered with the Recovery slider N CHAPTER 1 DIGITAL IMAGING BASICS WORKFLOW AND CALIBRATION N MOTAMMOM 21 21111172 1711211 215 79 E The shooting procedure for ACR is the same Once you have shot the exposure sequence open the RAW captures in ACR either from Photoshop or Bridge Make sure you have all your slider settings at zero and your tone curve set to linear and then do a white balance and synchronize all the captures before you start look ing for the best exposure ACR does not display the same Linear ProPhoto feedback numbers that Lightroom uses The engines are identical but the RGB numbers are not Instead it displays RGB numbers according to the workflow settings I recom mend using Adobe RGB as your preferred workspace Figure 1 20 This is the best compromise between working with the ludicrously wide ProPhotoRGB and the gamut constrained sRGB It is not so narrow that significant printable colors fall outside of its color gamut but not so wide a
49. your memory card place it in a card reader and mount the drive on your desktop 2 Copy the image files to a folder on your computer rename them and duplicate the files onto a separate hard drive as a backup 3 Verify the integrity of the backup This automatically verifies the first copy 4 Once you are satisfied that the files are OK you can reformat the card in the camera before shooting more images Of course you might not have enough time to copy duplicate and verify while you are shooting so you might need to have multiple cards on hand Always strive to have two copies of every image file at any one time Cards can be downloaded to the computer unattended so you can always have one copy on the computer and one copy on the card at the very least Some cameras have the capability to shoot to two separate cards in camera usually a CF card and an SD card so you ll have backups automatically as you shoot Having a computer on hand can be inconvenient for many photographers In that case consider using one of the portable self contained card reader hard drives Figure 1 4 as a temporary backup solution Charge Menu Display 4 0inch Photo Fine Premia Figure 1 4 Atypical card reader After all the images are shot and backed up they will have to be evaluated and worked on in some fashion Professional photographers tend to generate a high volume of images and file management can become a real issue Fortu
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