Originally Posted by JimP
I understand the idea of using a 4% pattern to avoid having the ABL circuit from affecting your gamma readings but does it do anything for color?
I think I may have figured out my own answer. Color patterns include lumanance which is basically how bright a color is. If you're you're using 100% intensity patterns, you run a chance of having the ABL circuit dim the pattern causing you to compensate by increasing the lumanace element of the color being adjusted. Therefore, you overcorrect and wind up with cartoonish color.
Am I even close?
I think this is why when calibrating colour you generally use 75 or 50% lum patterns.
Personally, i try to only use the CMS to ensure i hit the correct gamut points, then revert to saturation patterns to dial the colours in, usually with a compromise. Then final check with colour checker patterns to minimise the dE. Ive been using really small 1% patterns recently with really good looking results, but im gonna try APL patterns with a constant background between 20-30% when i get a few hours spare.