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I'm trying to do a touch up calibration on my RS 56. I altered the gamma to get it about 2.25. I noticed that the 100 IRE the blue is a little low 95% compared to 99% Green and 101 R and Error of 6.1. Last time I calibrated the set I change the gamma for Blue and Red to get it in line if it's 95IRE and below but I don't remember about 100IRE. It's been awhile. What do you change to make 100 IRE RGB balance? My Panasonic ZT60 had 100 IRE for adjusting the white balance.
 

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You can use the gain controls, which will also affect the rest of the greyscale but can be compensated by the custom gamma if needed.
 

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First... there is no such thing as IRE in digital video... not matter how many times you read it, it is ALWAYS wrong when you are discussing digital video. In digital video you use % white or digital values between 16-235 for consumer video sources (16-254 is more correct, but the information between 235 - 254 is not critical for good images.


Many sources tell you to MEASURE 80% and make it accurate with the Gain controls. This is INCOMPLETE information. The Gain control affects (approximately) 30% white to 100% white when you adjust it. (it might be 40% to 100% in some displays). The offset or bias control affects 0% to perhaps 70% white in most video displays. You will see less change at 30% than you will see at 100% when you adjust gain, but 30% will change (or maybe the change stops at 40%).


It is really wrong to measure 80% and assume your calibration is done. Because Gain and Offset/Bias overlap, you really MUST measure the entire grayscale, make adjustments to Gain and Offset/Bias then measure the ENTIRE grayscale again to see what happened. If the grayscale still needs adjustments, repeat the adjustment/measurement sequence as many times as necessary to get the best calibration.


The best calibration settings are the ones that give you the lowest errors for the ENTIRE grayscale. Not the settings that make 30% and 80% accurate. If you have dE=0 at 80% but you have dE=6 at 100%... that is NOT a good calibration. You need to make more adjustments and measurements and maybe you can get 80% dE=3 at the same time 100% dE=3.... that would be a much better calibration if 90%, 70%, 60%, 40% and 30% also have low dE errors.


The JVC projectors have more comprehensive Custom Gamma controls to make more grayscale adjustments, but the controls can be difficult to work with for beginner calibrators who do not understand what those custom controls do. Some of them adjust specific grayscale steps, but some may adjust intermediate steps like 85% or 15%... you have to be able to measure the intermediate steps then adjust the control to find the part of the grayscale that is adjusted the most when you use the custom gamma controls.
 
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