Originally Posted by MonarchX
CR = WP/BP. From setting to setting WP and BP need to increase by an identical amount to provide the same CR.
You keep demonstrating ignorance in your questions and statements. That's why I try to explain things to you. And, yes, the answers to your question are in what I post, but you're so self-absorbed you can't get past your hatred of my trying to help you get past this awkward stage. Like a 14-year-old who suddenly hates his parents for no good reason. It has been my experience that the best answers I've ever gotten to questions I've asked came from people who provided information... knowledge... and made me think about how that applied to my question. You asked a question without a yes or no answer - a question that required knowledge to understand the issues. If you knew as much as you keep telling us you know, you would not have needed to ask the question in the first place.
Lets just look at your statement quoted above... increase both black level and white level by the same amount provides the same CR...
No, it does not.
a) Black level = 0.03 fL white level = 30 fL CR = 1000:1
b) Black level = 10.03 fL whitel level = 40 fL CR = 3.99:1
All I did in case b was add an equal amount of light to both values, just like you said.. 10 fL added to black and white... which is an equal amount of light. Clearly the contrast ratios are not the same when you add an equal amount of light to black and white
For case b to have a 1000:1 contrast ratio with 40 fL for white, you could only add 0.01 fL to the black level (0.04 fL total). So in this case, as in all cases, the black level has far more influence on contrast than anything else. Just as I posted earlier. There is no universe I know of where 10 fL = 0.01 fL. (Yes, I'm being a smartass and you deserve it in this case).
The real issue here is that you keep thinking you are asking questions with yes or no answers and that's rarely possible when discussing calibration unless you ask something like "Are .3127 and .329 the right xy coordinates for d65?" .
And don't bring the 444 / 422 discussion into this - that whole thread was loaded with people (probably called in by you) to beat down the big bad ogre... who is still correct, by the way. None of your computer video boys could explain or even attempt to explain (or even acknowledge) why a page of colored text originating on a 420 Blu-ray disc looks pristine on a video display (in 422 mode) while a page of colored text from a computer degrades if the computer sends anything but RGB or YCbCr 444 - which was my point all along... 422 is not the problem, if there is a problem, it's coming from something other than 422 color decimation itself - like not doing it right and right includes being able to use 16-240 in Cb and Cr channels rather than being limited to 235 as the luminance channel is). But you (and the other lap dogs you called in) weren't interested in logic or knowledge, only in beating down the only voice of reason in a crap-storm of ignorance and assumptions. And this thread is headed in exactly the same direction.