Philips Magnavox 9P6034C 60" Rear Projection Television
Contents
1. CHT Video Projector Calibration Procedure CinemaSource 18 Denbow Rd Durham NH 03824 cinemasource com 800 483 9778 CinemaSource Technical Bulletins Copyright 2002 by CinemaSource Inc All rights reserved Printed in the United States of America No part of this bulletin may be used or reproduced in any manner whatsoever without written permission except in brief quotations embodied in critical reviews CinemaSource is a registered federal trademark For information contact The CinemaSource Press 18 Denbow Rd Durham NH 03824 CRT Projector Calibr ation Procedure CRT Projector Calibration Procedure SONY VPH D50Q CRT projector The procedure that Sony outlines in their technical documentation uses a method of converging that relies on merging the colors during the convergence procedure We have another method which we feel is more accurate This method relies on separating the two colors being converged by one line width and then matching the two images In our experience this results is a more tightly converged image and higher resolution n this section we outline a procedure that CinemaSource has written for aligning the Sony VPH D50Q Note that this procedure while specifically written for the Sony D50Q projector is generally applicable to other CRT projectors In particular the method of aligning the green reference Step 7 and aligning the colors to each other Steps 9 and 10 are uni2. When selecting the color pay attention to the white part of the picture displayed on the screen and note which color stands out compared to that of the monitor 4 Press the or key so that the white part in the picture on the screen looks the same as that of the monitor If the brightness does not look the same as that of the monitor adjust the other colors by pressing the ADJ R G or B key and the or key 5 Press the MEMORY key to save the adjustment data When using multiple projectors Input the same signal to the base projector and the projector to be adjusted Set COLOR TEMP in the INPUT SETTING menu to the same position on both projectors and then follow the procedures described above to make the black and white colors uniform between the base projector and the projector to be adjusted When adjusting the white balance use the external color monitor for the reference of the color To adjust the white balance easily without the on screen display press the STATUS OFF key on the remote control or set the STATUS option in the SET SETTING menu to OFF You can adjust the white balance more easily if you set the color level to MIN to display the black and white picture CRT Projector Calibr ation Procedure NOTES
3. also has a large collection of excellent video clips to view the finished work on The Video Essentials laserdisc and DVD are available for 49 95 AVIA AVIA Audio Video Interactive Aid is calibration software available from Ovation Software It currently is available as a CDROM based program that runs on PCs Macs and Windows NT machines and a DVD The AVIA program is powerful and multifaceted It is chock full of Ovation Software s AVIA program has two on screen interactiv e na Se E Patches Bun Only ae Colors oi Segment dynamic Pl 8 ico Section Below for Color Specifications Evaluates Saturation Hue Black Level The oliin ng ieee rofevionsh ps Pel VENTO bore woke UI Calibration easter to understand These relationships er true when both color decoding ana calibration are correct Video Test Pattern Generator test signal gener ators for calibrating an entire home theater A V system SPEAKER IDENTIFICATION CIEN Brogren E stir Tests Left Right Cable Rovorsel Steuer Placement surround Decoder Spooner Prose Left Right Cable Reversal Tt takas just one inadvertent lof right eabte reversal to chango the uu d ie ead ee tae GOANA 5 ie Audio Test Tone Generator CRT Projector Calibr ation Procedure version of the AVIA program will be available on DVD Because AVIA is a computer program one must have a way to connect a computer to the A V system being calibrated Note this
4. not a crosshatch pattern and cover the red and blue tubes so that the green image only is projecting 2 Adjust the SIZE control so that the image overscans 1 5 to 2 onto the black borders left and right 4 Adjust the SIZE control so that the image overscans 1 5 to 2 onto the black borders top and bottom EIIITIITIIIIIIITIIIIITIIIEITIIIIIITIIIIIIIITIIIIS E L L3 L L3 L L3 L L3 E E L E E L3 ps Screen with projected mage Same screen without projected overscanning onto the screen image but white dotted picture black borders 27 on all sides edge still shown Hote the The edge of the picture is shown overscan is 27 on all sides as awhe dotted ine CRT Projector Calibr ation Procedure STEP NINE Match the Red Image to the Green Reference Image E Overview In Step Seven you adjusted the green image so that it matches the screen The green image now becomes your reference standard to which you match the red image to This procedure is usually called Dynamic Convergence however we prefer the somewhat less technical term matching The procedure that you are going to undertake here is somewhat lengthy It will probably take you a hour or so to go through it We recommend that you take your time and perform this part with the room as dark as you can get it Procedure 1 Turn off the blue tube so that only the green and red are project
5. combined with the fact that you may cancel your factory warranty by opening up the set Well you get the picture The Calibration Tool Chest Not to long ago audio and video calibration procedures could only be performed by professionals who had access to expensive video test pattern and audio test tone generators Today that situation has changed because almost all of the test signals needed for calibration can be reproduced in the home via laserdiscs DVD discs and computer software programs The good news for do it yourselfers and A V professionals alike is that these programs are easily available and reasonably priced Here are three we recommend you look at Video Essentials Available from the Imaging Science Foundation ISF Video Essentials is the best known program for audio and video calibration Founded several years ago by industry veterans Joe Kane and Joel Silver the ISF is one of the first organizations to promote video quality issues in the consumer marketplace Video Essentials which the ISF offers on laserdiscs and DVDs is a wonderfully produced program It starts off by illustrating the need for audio and video calibration and then runs through several well animated technology tutorials After the proper ground work is laid it steps through the complete setup of a home theater s audio system and then a full video calibration procedure One of the nice features of the Video Essentials disc is that it
6. image without extraneous edges on vertical details Color Temperature You have probably noticed this term all over the video and home theater press the last few years and wondered what it really means Color temperature is the color shading of the black and white portion of a video image The term is borrowed from the academic physical sciences and relates to the color spectrum emitted by objects when they are heated to high temperatures For example some objects will glow red yellowish red hot when they are heated to high temperatures and white bluish white hot at even higher ones Because these objects glow different colors at different temperatures the term color temperature is used to describe the phenomena The color temperature of a video display is determined by the settings of the picture tube s drive controls These controls can be adjusted so the black and white image looks warm a low color temperature or a cool a high color temperature The resultant image can then be measured with a color analyzer the exact color temperature obtained The standard color temperature for NTSC broadcast in the United States is 6500 Kelvin Unfortunately adjusting the color temperature of a video display is not a do it yourselfer task It s best done by a professional because it requires special instrumentation a color analyzer and knowledge of how to make the gray scale track evenly at different brightness levels Ad
7. 09 0 0 06 09 090090 09 0909 0 0 0 00 00 0 00 090900 009 00 0 0090 60 00900 0 00 909090009090090092900299 9 don t be surprised if your contrast control setting isn t near the top of the range Most monitors and televisions cannot display a linear picture in the upper contrast ranges If you find this is the case with your monitor you have three options You can reduce the ambient light in the room you can stack another projector if you are using a front projector or you can turn it up anyway and run it out the linear range Many people do this anyway Color Saturation Filmmakers spend lots of time on color issues not only in the creation of a film but back in the lab during processing too They know that the color saturation level of images can be very important and is an essential element in the look of a movie When adjusting a display for proper color level by eye one is at a disadvantage because it s hard to tell what the director had in mind Fortunately calibrating for proper color saturation is easy What is required is a color bar pattern preferably a SMPTE color bar pattern Using a blue filter to view the color bars one can adjust the user color control so the relative brightness of the two outer pairs of bars white and blue match the small patches below them blue and white in intensity Tint The tint control of your monitor adjusts parameters in the color decoding c
8. Adjustment Screen Side view Horizontal H screw E 7e Moves horizontally Flapping i Adjustment Screen Top view CRT Projector Calibr ation Procedure STEP SEVEN Adjust the G reen Reference Image Overview In this section we will do the final aligning of the green image to the screen The reason that the green is done before the other colors is the green is the center tube and has the least geometrical distortion to compensate for It thus becomes the reference color that the red and blue images are matched to After this procedure is completed the green image as viewed via a crosshatch pattern should be level and parallel to all four edges of the screen Procedure 1 With the projector turned on and displaying a crosshatch pattern press the CUT OFF R B to prevent the red and blue tubes from projecting 2 Follow the steps outlined in the following pages Before adjusting The After adjusting the reference green reference green every line will be unlevel every line will be level tilted a possibly bowed referenced to a screen edge small degree CRT Projector Calibr ation Procedure Level this horizontal line with the SKEW Control Then remove the bow with the BOW Control Level this Control Then remove the pincushion with the PIN Control Start Here Level this horizontal line with the KEY Balance Control
9. Then remove the pincushion with the PIN balance Control Make the height of the boxes from top to bottom the same with the LIN Control lines should be straight and parallel Level this vertical line with the SKEW Control Then remove the bow with the BOW Control Level this Control Then remove the pincushion with the PIN Control CRT Projector Calibr ation Procedure Level this vertical line with the KEY balance Control Then remove the pincushion with the PIN balance Control Make the width of the boxes from right to left the same with the LIN Control END RESULT All the horizontal and vertical lines should be straight and parallel CRT Projector Calibr ation Procedure STEP EICHT Adjust the G reen t Image Overscan OVERSCAN Overview Overscan refers to the amount of video picture that runs off or overscans the borders of the picture The general rule is that you want approximately 2 of overscan on all four sides so that image artifacts such as bright lines and digital data are not seen The figure below illustrates this Procedure 1 Display a steady video image
10. a home theater room If you examine the drawing you will see that when a projector is square to the screen it will be positioned along the screen s centerline and the distances X and Y will be approximately equal The actual distance that a projector is positioned back from the screen F or C is determined by the manufacturer and is stated in their installation manual Procedure 1 Verify that the projector is positioned the proper distance from the screen by measuring the C or F dimension and compare it to the manufacturers specifications The margin of error allowed in this measurement is generally 1 2 inches In other words if the installation manual says that the C dimension should be 103 and you place it at 105 you should still be able to converge the projector 2 Verify that the projector is square to the screen by measuring the X or Y dimensions These should be within approximately 1 of each other 3 Make sure that the downward angle of the projector see the diagrams on the following page is not too severe If your installation is off the charts pointing down the wall too far you may have a problem adjusting the convergence because the controls will run out of range The relationship of a video projector to the projection screen The F and C dimensions come from the manufacturers installation liter ature CRT Projector Calibr ation Procedure SONY D50Q INSTALLATION DIMENSIONS Erik Cath
11. arm by adding some red or a little cool by adding some blue The resultant image can then be measured with a color analyzer and a specific color temperature given for each setting The standard color temperature for NTSC broadcast in the United States is 6500 Kelvin Most video projectors allow you to change the color temperature internally This is difficult to do without a reference however so we recommend that you only adjust these controls if you are doing fine adjustments CRT Projector Calibr ation Procedure Adjusting The Color Palance On The Sony D50Q SONY VPH D50Q Setting the white balance 1 Press the MENU key select INPUT SETTING with the 4 or key then press the ENTER key The INPUT SETTING menu is displayed 2 Press the or key to select COLOR TEMP then press the ENTER key 3 Press the or key to select the desired color temperature then press the ENTER key s W COLOR TEMPERS n CLAMP AUTO aca OU SHIFT WI D SYNC SEL A COMPONENT E lil SMPT sr O SYNC OSC 1 y aQ ses GE on Gan Normally set to 6500 Select the appropriate color temperature according to your application and the picture source 4 Press the MEMORY key to save the adjustment data Adjusting the white balance If you wish to make the color of a particular input signal eg HDTV system picture uniform to that of the color monitor you can adjust the white balan
12. ce Display the same input signal on the projector and the monitor Adjusting the black level BIAS adjustment 1 Reset the CONTRAST level to 80 and BRIGHT level to 50 For details see Adjusting the Picture Quality on page 103 EN 2 Press the W B BIAS key The PLUGE pattern appears Press the PATTERN key repeatedly to display the external signal 3 Press the ADJ R G or B key to select the color to be adjusted When selecting the color pay attention to the black part of the picture displayed on the screen and note which color stands out compared to that of the monitor CRT Projector Calibr ation Procedure 4 Press the or key so that the black part in the picture on the screen looks the same as that of the monitor If the brightness of that part does not look the same as that of the monitor adjust the other colors by pressing the ADJ R G or B key and the or key 5 Press the MEMORY key to save the adjustment data Adjusting the white level GAIN adjustment 1 Reset the CONTRAST level to 80 and BRIGHT level to 50 For details see Adjusting the Picture Quality on page 103 EN 2 Press the W B GAIN key When the GAIN adjustment is followed by the BIAS adjustment the external signal appears automatically When you start with the GAIN adjustment the stair step pattern appears Press the PATTERN key repeatedly to display the external signal 3 Press the ADJ R G or B key to select the color to be adjusted
13. e projector is ceiling mounted then loosen the horizontal and vertical adjustment hardware most projector ceiling mount brackets allow a limited amount of horizontal and vertical movement and swing the projector until it is approximately centered on the screen Procedure 1 With the projector turned on and displaying a steady video image a laserdisc or DVD on freeze frame for example turn off the red and blue tubes so that only the green is projecting 2 Move the projector around horizontally and vertically so the green image is centered on the screen The figures below illustrates this Note a favorite installers trick used to center the green image on the screen is to underscan the borders with the height and width controls This allows you to easily see the position of the image 3 If the projector is ceiling mounted tighten the projector pivoting hardware to hold the projector in place but don t tighten the hardware down permanently because you may come back later to do some fine adjusting of the projector position When you start the green After you finish the image usually will not be green image should be centered on the screen centered on the screen CRT Projector Calibr ation Procedure STEP FIVE JR Adjust For Segmentation Focus Adj ust The Optical m in Vertical Lines NH Focus Hint Vertical Segmentation Overview The video images scanned in the projector tubes are o
14. er Distance drop i in ad PE mi 145 Jaki 2 rom ceiling I I C Distance irom ihe center ci the projector ceiling mount bracket ta the projection screen surface T Distance irom the top cf the projected image tothe horizontal plane that the projector base is mounted hung from H Height of the projected image SCREEN SIZE ASPECT diagonal CRT Projector Calibr ation Procedure 9 0 9 906 06 0909 0 0 0 0 00 009 00 0 0 00 00900 00 0 090 00090 009090 00 000009000090 090900900090090929099 9 STEP TW Change the projector over to correct scanning polarity Switching The Scan Connectors 180 Degrees x ix Connecting position of Polarity switch ition Giarity switen positio the polarity connectors i Lens side Factory j Lens side preset i Factory preset Installation Position of the Connecting On screen display methods switch position of the by default See connectors the next page Front projection L L Correct floor Front projection B B Cl ceiling Rear projection L B Al floor Rear projection B L B ceiling Others Display letters on the screen so that you can determine which changes to make CRT Projector Calibr ation Procedure STEP THREE Center the Green Image in the tube Overview The video images scanned in the projector tubes should be rou
15. es What s interesting though is that while the technology has changed just a bit the essence of story telling remains the same Filmmakers still use the best technology at their disposal to tell their story However in contrast to the ImagingScience FOUN DATION user controls that are easily accessible via the remote control or from the front panel of the television monitor itself These controls generally include functions such as brightness contrast color tint and sharpness On some video displays you may find additional functions such as color temperature image centering and picture size adjustments on some widescreen displays All of these controls are referred to as user controls for good reason they are designed for easy access so that the user can adjust the display s image to suit his or her tastes The second level of adjustment involves controls that are NOT easily accessible to the user These factory adjustments are either located on hidden on screen service menus or are physically located inside the cabinet of the display device The reason that these controls are not user accessible is that they are designed for use by trained technicians during the display s manufacturing process and or during any necessary repair procedures However as you probably surmise adjusting some of these factory controls may be necessary to calibrate a video display for best image reproduction This presents a dilemma is
16. est done by a technician It is usually an internal control and on some projectors may require special techniques Rear screen and front screen projectors not only have three of these electronic focus adjustments one for each tube they also have optical focus adjustments Optical focus refers to the adjustments performed on the projection lenses LCD and DLP based projectors are designed for user adjustment but CRT based units are not The overscan of a video monitor is the amount of image that ie lost off the edges of the screen Properly adjusted monitors should have 10 overscan or less Overscanning as viewed on a front video projector An Overscan Pattern CRT Projector Calibr ation Procedure A Quick and Easy Video Calibr ation Procedure n your video projector you have several user Qs brightness color contrast tint and sharpness that can be adjusted for the best video picture You can adjust these for personal preference but in reality the settings of these video parameters are tightly defined on the creative end of television programming If you want to calibrate your video projector to the studio settings get a copy of the Video Essentials LD or DVD test disc and proceed as such 1 Brightness Control The brightness control on your monitor adjusts the overall brightness of the video image Often referred to as the black level control It affects the entire image from the deepest blacks
17. et will have the contrast control set at the point just before the bending occurs and you may find this is too dim a picture for you If this is the case you have three alternatives Blache Ahar bar 5 IRE 5 jet bel cav Ihre kara of Ere backgroud sta de Brightress Control Correct y Adjusted CRT Projector Calibr ation Procedure Proper Contrast Control Adjustment Proper Adjustment of the contrast Gontml Reduce the ambient light in the room If you are using a front projector add another one Turn it up any way and run out of calibration Many people do this anyway 1 2 3 3 Color Control Advance the Video Essentials disc to the SMPTE color bar pattern as illustrated below Those of you late night television junkies will recognize this pattern The color control of your monitor adjusts parameters in the color decoding circuitry Most people adjust it for good flesh tones This approach actually isn t so bad because the human eye is in fact very good at judging flesh tones with accuracy However from a professional broadcasting standpoint subjective measurements like this must be standardized and the reference recording disc provides a way to do this Imp oper Adjustment of the Gontrast Gontml Pull out the blue filter supplied with the disc The blue filter is designed to block the red and green images so you see just the blue one Now adjust the color control so the relative brightness of the oute
18. fferent Aspect Ratio Memories D Standard 4 5 images 2 16 9 Letterboxed images 3 16 9 anamorphic images Others may be needed for wider letterboxed and anamorphic images and DTV Pop up menu When using the Sony D50Q is used to project video signals through the composite or s video input ten memories are available Each of these can be used for a separate aspect ratio Es VIDEO MEMORY 4 Q Omm opum When using the Sony D50Q is used to project RGB video signals from a video processor the projector is used in 5bBNC Mode This allows you use the Switcher Index buttons on the Switcher Index Buttons remote control for different aepect ratio memories CRT Projector Calibr ation Procedure Video Dieplay Calibration brilliantly in the sky overhead and the campfire is blazing away You ve just finished a hearty meal of roast mastodon and you and the rest of your loinskin clad band are settling in for a good round of story telling After everyone quiets down shadowy figures wearing animal masks and draped in fur emerge from the forest and begin telling tales of adventure bravery and sorrow For the rest of the evening barely a grunt is heard from the audience magine it s a cool summer night the stars scintillate Today instead of using rocks Sticks and dead animal parts filmmakers generally prefer to use motion picture film and movie sets to tell their stori
19. first involves adjusting and how far the technician has to travel but the results can be well worth it On the other hand for those who want to save money or just prefer to adjust their electronic gear themselves there s no reason not to proceed with the display s user controls You can calibrate these controls easily using many of the available software packages As for the internal factory controls or service controls on hidden menus As you probably anticipated we ve got to toss in the boilerplate about adjusting factory controls Attention Do It Yourselfers even though factory controls can effect the level of performance of your video display they are hidden for good reason They can be very complex to adjust and may require special instrumentation CRT Projector Calibr ation Procedure 8 ta Audio Video Interactive Aid AVIA is available from OVATION SOFT WARE 200 Putnam St Marietta OH 45750 614 373 6212 VIDEO ESSENTIALS is available from the IMAGING SCIENCE FOUND ATION 3257 Harrington Dr Boca Raton FL Tests Navigation Foreground pre Polarity Options Heb DISPLAYMATE is available from SONERA TECHNOLOGIES PO Box 565 Rumson NJ 07760 908 747 6886 33496 561 997 9073 to calibrate properly you can literally cause more harm than good if you adjust these controls by eye Also all of today s CRT based displays and televisions contain some pretty high voltages and
20. ghly in the middle of each tube If an image scans off center too much as illustrated below it may be difficult to convergence the projector In the worst case if the image scans off the phosphor and strikes the glass envelope it can cause all sorts of problems and possibly shorten the life of the tube Procedure 1 With the projector turned on turn the brightness and contrast controls down so a very dim image is projected 2 Look in the front lens on the green tube and verify that the green raster is approximately centered in the middle of the phosphor target refer to diagram below If the image is approximately in the center then verify that the red and green images are roughly in the center also 3 If the green image is NOT in the center then use the centering controls Zone Adjustments to center them 4 Repeat the same procedure with the red and blue tubes if their images are also not centered CEN TERNG CORRECT CENTERING INCORRECT Locking in he frontlens ofthe green Ic FOR The green video picture ube you should DRUM image is not see the video image JARRE UJ centered on approximately centered NS fie phosphor on the phospno f CRT Projector Calibr ation Procedure STEP FOUR Center the G reen Image i on the screen Overview The next step after verifying that the green images is centered in their picture tubes is to physically move the projector so the image centered on the screen If th
21. he Separation of the red and green lines in the middle M equal to the top T and Separate the middle red and green vertical lines by a few line widths with the bottom B with R CENT the LIN control control E mmama Green liz E Bed liz i Move the red lines directly over the green with the R CENT control Match the tilt of the red line to the green with the SKEW control RESULT All the red and green horizontal lines lay on top of each other to form horizontal yellow lines Remove the bow with the BOW control Geen lings bw F d lins Match the tilt of the right red horizontal line to the green with the KEY control Then remove the pincushion with the PIN control Match the tilt of the left red vertical line to the green with the KEY BALANCE control Remove the pincushion with the PIN BALANCE control Make the separation of the red and green lines on the Left L and the right R equal with the SIZE control CRT Projector Calibr ation Procedure Make the separatio
22. ing and put on a crosshatch pattern 2 Closely follow the steps on the following three pages When you have finished this red matching procedure you should have a yellow crosshatch pattern with a minimum of color fringing in the corners Note Take your time Our experience is that few are good at converging a video projector the first time around but do a lot better after a few attempts CRT Projector Calibr ation Procedure I er 9 0 06 06 0909 0 0 0 00 009 00 0 00 00090 09 0 090 00090 0 009090 0000009000090 009090090009 0090929099 9 Start Here UN Separate the middle red and green horizontal Then remove the IH A pincushion with i lines by a few line the PIN control Il widths with the CENT R iu control Green liz Fod lin Match the slope of the top red horizontal line to the green Match the slope of the red line to the green with eee come KEY BALANCE control Remove the Remove the bow pincushion with with the the BOW PIN BALANCE control control mmama Gres lings Ped linis 5 Make the separation of the red and green lines on the top T and the bottom B equal with the SIZE control Match the slope of the red bottom line to the green with the KEY control CRT Projector Calibr ation Procedure Make t
23. ircuitry for accurate color hues Most people adjust their tint controls for good flesh tones and actually this approach isn t so bad because the human eye is very good at judging flesh tones However there are test patterns to objectively set tint controls The most common is again the SMPTE color bar pattern with the blue filter Adjust the tint control so the cyan and magenta bars match the magenta and cyan patches located directly below them in brightness When this is accomplished you should find that your flesh tones are right on the money Sharpness In a pure sense you actually want the sharpness control to be off period Sharpness controls add extraneous information to a video images in an attempt to make them look sharper An analogy would be the tone controls on an audio receiver Tone controls do nothing more than boost certain frequency ranges so the audio sounds better certainly not more accurate Video sharpness controls do the same thing they peak certain frequency ranges in order to create the illusion of a sharper picture To view what happens with your sharpness control put on a luminance multiburst pattern As you adjust the control you ll notice that the middle frequency bands become brighter and brighter This is because the sharpness control is actually boosting the middle picture frequencies So how do you adjust the sharpness control Adjust it as little as possible and look for a subjectively better
24. is commonly done with via interface cards or scan converters The AVIA program is powerful and multifaceted It is chock full of everything from highly detailed audio video technology tutorials to completely interactive test pattern generators Of special interest to those involved in home theater construction are two sections One is an interactive on screen calculator in which you plug in your video system specifications size of display aspect ratio etc and it calculates the proper seating locations for the audience Another is a calculator which calculates and plots sound resonance modes in home theater rooms of different dimensions For those who simply want to calibrate their home theater AVIA will step you through the entire procedure interactively Advanced users and professionals can skip right to two on screen test signal generators one for video test patterns the other for audio signals The AVIA software program is priced at 59 95 for the computer software and DVD versions DisplayMate Sonera Technologies are the folks that produce the test patterns used in the famous INFOCOMM projector shootouts Their DisplayMate test pattern software is very popular in the computer industry It is used by virtually every computer publication for the testing of computer monitors and by most manufacturers of computer display devices Their product line currently consists of four packages DisplayMate DisplayMate for Windows Dis
25. it necessary to call an A V professional to calibrate your home theater display or can you do it yourself Well it depends Having an audio video professional calibrate your display is probably the best route if you are unfamiliar with electronics and video technology A V professionals practice the art frequently and have often received specialized training via professional seminars Yes it can be expensive from 150 to 400 for a complete job the storytellers of Paleolithic times contemporary filmmakers rely on technology not only to create their vision but to reproduce it for the The Imaging Science Foundation maintains a nationwide team of dealere and installere trained to calibrate video displays factors involved are what kind of display you have whether you a want a tune up or an overhaul audience And they count on the ANN reproduction technology employed to recreate their vision intact This is why calibration as a principle is important Calibration of audio video and film equipment is a way of insuring that the director s vision is being reproduced in exactly the way he or she intended it to be In this article we will look at the calibration of video display devices in home theaters and examine some of the tools available to complete the task Who Ya Gonna Call Calibrating a video display requires adjusting many controls and it is important to know that there are two levels of expertise involved The
26. justing a monitor for correct color saturation and hue reproduction is easily done with SMPTE color bars and a blue filter SMPTE Color Bars Color Bars viewed through Blue filter CRT Projector Calibr ation Procedure Overscan How would you feel if someone were to tell you that 15 to 2096 of your video picture is missing Well this is exactly what happens with excessive raster overscan Video display manufacturers typically overscan their displays to hide the uneven edges of the raster it s normal practice Of course the amount of picture information you lose depends on your particular monitor or television Some picture tube type displays overscan a great deal of the image usually inexpensive ones With rear screen televisions less is usually lost because the scanning circuitry is more advanced and the overscan can be adjusted tighter With front projectors you lose the least because you can project 100 of the raster you only lose what actually scans onto the black borders of the Screen see our diagram To judge the overscan of your monitor use an overscan pattern Adjusting it however generally requires a professional the controls are sometimes on on screen menus but usually are located deep inside the cabinet Convergence The method by which modern color television works is by adding three primary colors of light red green and blue in different proportions to create the full spectrum we
27. n of the red and green lines in the middle M equal to the left L and right R with the LIN control Move the red lines directly over the green with the R CENT position control lines eee Gron lings Ped lines CRT Projector Calibr ation Procedure Fine Tuning le Done Via The Zone Adjustments Adjust red ZONE after the red lines have converged with the green lines by performing the adjustments J to i 1 Press the ZONE key The 9 x 9 HATCH pattern and the cursor appear 2 Press the POSITION keys to select the part to be adjusted When you press the key the cursor moves in the numerical order as illustrated When you press the key the cursor moves in the reverse order The selected position number appears at the upper right corner If you press the ZONE key again in ZONE adjustment mode you can move the cursor to the desired position with the 4 keys When you press the ZONE key again after selecting the position the projector enters the adjustment mode of that postion Adjust the red line distortion in the cursor positioning area with the arrow keys After the adjustment is complete press the MEMORY key to save the adjustment data i CRT Projector Calibr ation Procedure STEP TEN Match the Blue Image i to the Green Reference Overview The
28. object of this step is to match the blue image to the green reference crosshatch The procedure is exactly the same as matching the red except the blue convergence controls are used Procedure 1 Cut off the red tube so that only the green and blue are projecting 2 Use the same procedures as used in the red to green matching section When you have finished this blue matching procedure you should have a light blue actually Cyan crosshatch pattern with a minimum of color fringing in the corners After adjusting all the registrations for the green red and blue signals save the adjustment data as the standard data for the projector 1 Hold down the MEMORY key for more than 5 seconds The adjustment data is saved in the memory as the data for the frequency selected in INT OSC PATTERN of the SERVICE Wh en you are SETTING menu and the projector enters the standard data saving mode finished the convergence is savins No key may be applicable MEMORY DATA during the indication of saving is this mode complete Save The Final Adjustments The registration data aQ os Dg en Xi 2 Press the or 4 key to select YES then press the ENTER key All the registration data will be converted into internal signal data and are saved as standard data CRT Projector Calibr ation Procedure LAS I UR E A graphics projector show be STEP ELEVEN adjusted for a minimum of three aspect ratios Setting Up Di
29. playMate for Windows Video Edition and DisplayMate Professional DisplayMate for Windows Video Edition the version of interest to most home theater enthusiasts is basically a ultra talented test pattern generator It offers 116 test patterns many of which are available nowhere else A very handy feature is that each of DisplayMate s test patterns includes an information window that explains what the pattern is for how it works and what effects to look for With the Adjusting the brightness control of a video display device is very important for proper black level reproduction If adjusted incorrectly important shadow details can be lost from the image Bl cher than black bar 5 IRE Lighterthandlack bar 10 IRE Erighitre zs Control corre cp Adjusted convergence of TV and PCs coming closer every day DisplayMate is a way of assuring that the two work together well DisplayMate for Windows Video Edition retails for 99 95 Video Calibration Control by Control Video displays are remarkable complex devices To calibrate them requires the adjustment of many user controls and if an A V professional is involved the adjustment of potentially dozens of internal controls Here are some of the ones you should know about Brightness Control If you are a film buff you know that many directors thrive on dark scenes They often have shadowy figures appearing and disappearing into murky darkness It is the
30. ptically focused onto the screen via the projection tubes lenses These need to be precisely adjusted in every installation Procedure 1 Turn the projector on and display the H focussing test pattern 2 Adjust the rear lens focusing screw for the best focus in the screen center 3 Adjust the front lens focusing screw for the best focus on the screen edges Adjust For Sharp Focus in Screen Center Blue Center GreenCenter Red Center Focus Focus Focus Blue Edge Green Edge Red Edge Focus Focus Focus Adjust For Sharp Focus on Screen Edges CRT Projector Calibr ation Procedure STEP SIX Adjust The tubes Flapping The flapping adjustments allow you to map the tube faceplate precisely to the screen for best focus Overview The video images scanned in the projector tubes are optically focused onto the screen via the projection tubes lenses After the tubes are optically focussed the angle of the lenses needs to be adjusted for best focus Procedure 1 Turn the projector on and display the H focussing test pattern 2 Adjust the green V screw for the best focus across all four screen edges see diagram above Normally you will not have to adjust the green H Screw 3 Adjust the red and blue V screw and H Screw for the best focus across all four screen edges see diagram above Moves vertically Vertical V screw D gt Fla pping Focal surface
31. r pairs of the large and small bars match in intensity See the diagram below 4 Tint Control Setting the hue control uses the same pattern as the color saturation adjustment but what you do here is adjust the tint control so that all the bars indicated are the same brightness see below When this is accomplished you should find that your flesh tones are right on the money 5 Sharpness Control Adjusting the sharpness control is more subjective than the other controls In a pure sense you actually want the Both upper and kawar bars mach in inbare dbi COLOR Control Ince mect hy Adjusted siewed Thru Hue filter COLO RE Conr ml Comect y Adjusted eewed thru blue Ata E rarm Yaon Sky BR COLOR Control Comectly Ad justed iewed with ne filter CRT Projector Calibr ation Procedure These four bop bars are dierent inberci tee These four bop bers are equal irteredy Proper Tint Control Adjustment TINT Gentre TINT Gentre inco meetly Adjusted Gorrecth Adjusted sharpness control to be off because it behaves like tone middle picture frequencies in this area Well designed controls on a receiver Tone controls distort the audio so picture controls do not boost the higher frequencies it sounds better not more accurate Video sharpness because this would boost fine pitch picture noise in controls do the same thing but most people simply like the addition to picture details effect they provide a s
32. refore critical to have a video image s black level match the film release s black level or you can miss story details Thankfully control of the black level of the picture is a close as your monitor s Brightness or Black Level control The standard pattern for adjusting black level is PLUGE Picture Line Up Generating Equipment pattern that allows you to set the black level properly The procedure is simple Adjust the brightness black level control until you can just see the darker than dark bar melt into one to the next to it Contrast Control When you adjust the contrast control on a CRT based video display device for best peak whites you aren t actually calibrating the display s contrast range what you are doing is making sure the monitor behaves itself The problem is that when the user contrast control is set too high the high voltage power supply can run out of it s linear operating range and when this happens bright images can lose focus and picture geometry can shift The standard pattern used to visualize a high voltage supply s linear range is a needle pulse pattern see our diagram Adjusting the contrast control for best peak whites with this pattern is simple Just turn up the contrast until the pulse starts to distort However EM acier this rel ect bar SRE amp jet Eo Ihre Keyed off Eee bachegnoc ned spe Erigh tress Control Correct Adjusted CRT Projector Calibr ation Procedure 99 9 9 0 0
33. see on the display In order to produce a sharp tightly converged image the three colors need to map each other precisely across the entire screen Technicians generally use a crosshatch pattern to view the The Video Essentiale disce hav e some specialized patterns which are useful to judge color decoder performance This Snell and Wilcox Zone Pattern is one of them color mapping and look for convergence errors Now before we start a witch hunt a disclaimer is necessary All video displays have some amount of misconvergence particularly in the corners If you put up a crosshatch pattern and see color fringing don t be terribly alarmed It is normal on CRT based devices and LCD and DLP videoprojectors and could well be with in the factory specifications for convergence error However if your display is a rear screen television or a CRT based front projection monitor and you see a severe amount of color fringing call in an A V technician He or she should be able to tighten it up for you m ii ri a Focus All CRT based video displays have focus adjustments in fact some have two different types Let s start with direct view monitors Inside the picture tube of all direct view monitors is a series of electron gun elements designed to focus the electron beam so it produces a sharp image This is commonly referred to as the set s electronic focus adjustment Here again adjusting electronic focus is b
34. to the peak whites Generally the manufacturers of video display devices set the brightness control so when they are in the middle of the adjustment range mid range when they are calibrated for proper blacks You can check the accuracy of the manufacturers settings by freeze framing the Video Essentials Disc on the Picture Line Up Generating Equipment PLUGE pattern The procedure is to adjust Ela cher Inan Black bar E IRE Lighbartharblack bar 10 IRE Proper Brightness Control Adjustment Brightress Control moore cy Adjusted the brightness control until you can just see the darker than dark bar melt into one to the right of it At this point you have the set calibrated properly for black level See the illustration below Note Many DVD players are set to 7 5 IRE and cannot display the darker than dark bar 2 Contrast Conirol The contrast control can be set using the Needle Pulse Pattern This pattern has a large black area on top anda white area on the bottom Start with the contrast control turned down and slowly adjust it until the thin line on the left of the image starts to bend At this point the set is having HV sag problems and the setting of the control should be restricted to this level Don t be surprised if your contrast control setting isn t even near the top of the range Most monitors and televisions cannot display a linear picture in the upper contrast ranges A properly calibrated s
35. ubjectively sharper image To view what happens with your sharpness control So how do you adjust the sharpness control Adjust it for advance the Video Essentials disc to a standard a subjectively best image with least over enhancement multiburst pattern You ll notice that the middle bands start to become brighter when you turn the control up This is because the sharpness control is actually boosting the Exactly What Is Color Temper ature Anyway You have probably seen the term Color Temperature all over the home theater consumer press the last few years Here s what it means the color temperature is the color shading of the black and white portion of a video image The term color temperature is borrowed from the academic physical sciences and relates to the color spectrum emitted by an object when it is heated to a high temperature For example some objects tend to look white bluish as in white hot and others tend to look red yellowish as in red hot depending on how much they are heated Because these objects glow a different color at different temperatures the term color temperature is used If you take a television and adjust the user color control to a minimum you will see a picture that seems black and white but really isn t it is colored ever so slightly The color you see is determined by the settings of the picture tube s drive controls These controls can be adjusted so the black and white image is just a little w
36. versally applicable to all CRT projectors STEP ONE VERIFY THE CORRECT SCREEN PROJECTOR DIMENSIONS 4 STEP TWO VERIFY THE CORRECT SCANNING POLARITY 6 STEP THREE CENTER THE GREEN IMAGE IN THE PICTURE TUBE 7 STEP FOUR CENTER THE GREEN IMAGE ON THE SCREEN 8 STEP FIVE ADJUST THE OPTICAL FOCUS 9 STEP SIX ADJUST THE TUBE FLAPPING 10 STEP SEVEN ADJUST THE GREEN REFERENCE IMAGE 11 STEP EIGHT ADJUST THE GREEN REFERENCE IMAGE OVERSCAN 14 STEP NINE MATCH THE RED IMAGE TO THE GREEN REFERENCE 15 STEP TEN MATCH THE BLUE IMAGE TO THE GREEN REFERENCE 20 STEP ELEVEN CENTERING THE USER POSITION CONTROLS 21 CRT Projector Calibr ation Procedure STEP ONE Verify The Correct l Screen Projector Dimensions V Overview CRT Video projectors are designed to be positioned a specific distance from the the screen and square to it s surface In the diagram below we show an overhead view of a projector in
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