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I’m trying to calibrate my Samsung qled q60t.
First step on the software says to adjust brightness and rgb offset to achieve black level target.
Second step says adjust temperature and rgb gain to achieve the white point / white leve targets.
Third step is white level. Which says to adjust contrast and rgb gain to achieve the target.
And last step is black point / black level which says to use just rgb offset to achieve the targets.
The thing is. Doing on this order… After finish IF I try to test the first step or second step and etc, I get wrong results.
So# should I do step by step and at the end if I back to first, second or third step the will look wrong and this is normal? I just should ignore and start calibration?
Or when u d all the things right, doesn’t matter what test you do (1, 2, 3 or 4th step) you always gonna get the green target result? Because this# looks impossible to achieve.
Disclaimer: I know a bit about color spaces from a theoretical standpoint, but have only recently gotten into display calibration.
I may be able to help you more in a few days, because my in-laws have recently gotten a Q60T and I will be able to have a look at it, right now I can just guess.
The relationship between the different settings (contrast, brightness, gain) is not always exactly the same for different devices. Sometimes “Brightness” is just adjusting the backlight and does not relate to calibration (apart from the luminosity of the white point) at all, although most of the time it is a “brightness offset” which can exchange black vs white crush if contrast is too high and there is a separate backlight control. Sometimes contrast is like a gain (contrast = 0 => screen black), sometimes it is a relative contrast (contrast = 0 => screen 50% gray). The brightness offset might be applied before or after the contrast so adjusting one might modify the other or vice versa.
I would try to experiment with the order of settings to see how it is possible to adjust everything such that later adjustments don’t break the earlier results, while taking into account the natural limitations of the display.
I would start by setting brightness/contrast such that there is an almost zero amount of black/white crush while maximizing contrast. Then i would adjust the rgb gains/offsets to set color temperature at 80% and 20% gray by alternating between those and making minimal adjustments each time (80% should be mostly affected by gain, 20% by offset. a bit of cross influence can be mitigated by iteration). Maybe you will even have to start from the very beginning (because rgb adjustments may modify black/white crush) and repeat those steps once or twice to settle everything in. Then set the backlight to whatever white luminosity you would like to have.
The reason I suggest 20% and 80% is because near 0% and 100% displays may have intrinsic deviations and there is no use in calibrating the extremes to fix the non-linearities of the display, while possibly throwing off the mid-tones which will make up a good portion of the content actually watched. The left-over deviations <20% and >80% may be corrected through LUTs if the playback device supports it.
Thx man. After a while I could adjust each parameter and got a perfect result.
I learned too that normally u should not bring up rgb gain and down rgb offset. That helped a lot.
