[frizzo]

Well, I was tweaking my projector last night according to Dave Boswells percentages and I had some things that confused me. As far as RGB Gain and Bias goes, what do these mean? If I want the picture to be more blue, what do I do, do I up the B Gain or B Bias? How do these numbers work?


Also, has anyone done these percentage tweaks and noticed a loss in shadow detail? I tweaked it last night and watched the first 15 minutes of Moulin Rouge and it felt like there was more contrast but possibly not as much shadow detail. This could just be my mind playing tricks on me, but I am not sure. Could the tweaks to the Gain and Bias affect contrast and shadow detail?


Last thing, what is a good movie for true color representation? I watched Matrix last night, and I swear the majority of that movie has a green tint because of the lighting. I watched Moulin Rouge and eveything was really warm and gorgeous...but what if the director shot the entire movie with a bias towards red. So I need a movie that has real acurate life like color to calibrate to by eyesight (too poor to get Avia yet, someday!). Let me know what you guys think! Thanks


|..frizzo..|

 

[jwtseng]

Why don't you get AVIA or one of the other calibration discs. They usually have fancy color bars and patterns and grayscale windows that will allow you to calibrate your projector to perfection.

 

[Mark Hunter]

Quote:

If I want the picture to be more blue, what do I do, do I up the B Gain or B Bias? How do these numbers work?

The Bias controls are used to adjust the low end of the gray scale, and the Gain controls are used to adjust the high end.


Of course, the goal is to have a monochromatic gray scale that matches the natural coloration of nature (illuminated by the sun...or D65). Once you have a perfect gray scale, all of the "color" information is simply added on top of that. If your gray scale isn't correct, adding the color on top makes the resulting image not correct and not as "life like" as it could be.


Between the R,G,B Bias and R,G,B Gain controls (six controls total), you have the adjustments to be able to get the entire grayscale correct.


If you wish the picture to have more Blue in the high part of the gray scale, you need to increase the Blue Gain control or reduce the Red and Green Gain controls, depending on whether your luminance needs to go higher or lower at the high end (which are separate criteria related to the calibrated image related to "gamma" and "white crush").

 

[SRR]

Quote:

I watched Matrix last night, and I swear the majority of that movie has a green tint because of the lighting.

If you didn't already know the green tint to the matrix is supposed to there when they are in the "Matrix" when they are out of the matrix its supposed to be a much more even color balance.