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What’s the actual contrast in your display?
According to measurement report 5000:1 (attached).
Aim to 2.4 relative if using a fake contrast profile…. there is no point using Rec1886 with such data.
So settings as attached? With these the image still gets desaturated in darker scenes, but less than before. What is the difference between bt1886 2.4 and custom gamma 2.4?
Should I disable vcgt, as suggested before in this thread?
What do you mean by “with such data”?Sorry for my noob questions, I am here to learn.
BT1886 will do black compensated and the profile is black compensated so it is double black compensated. 2.4 gamma is not black compensated except when relative and will be fine with a 5000 contrast ratio. Low contrast 1000 and less and high gamma 2.4 is a challange. It looks good though. High gamma gives less nits in blacks. Gamma is critical to looks. Very odd that without the 3d lut it looks fine. Could be the meter is wrong. Do you have a blue, red or green filter built in to the screen to use with mp4-2c in the AVS HD709 link. You could see without the 3d its fine and with its wrong.
Sorry HDR is another animal and can not use color bars or color steps.
What’s the actual contrast in your display?
According to measurement report 5000:1 (attached).
Aim to 2.4 relative if using a fake contrast profile…. there is no point using Rec1886 with such data.
So settings as attached? With these the image still gets desaturated in darker scenes, but less than before.
Usually we use detailed profiles for creating LUT3D (XYZLUT, no BPC), ones that store display behavior with all its limitations, including contrast.
For every day clor management and image editing, your matrix curve profile with fake infinite cobtrast is the way to go with VA, IPS and such. same for serious image editing *on a good behaved display* (one which verification against a matrix profie gives low dE errors) unless you limited contrast intentionally to <500:1 because softproofing with raised UI black in PS.What is the difference between bt1886 2.4 and custom gamma 2.4?
On your fake infinite contrast profile should have no differences on unless there was some bug or misconfiguration
bt1886 will change gamma to adapt to actual black point, so bt18886 g2.4 on an 1000:1 IPS may look like 2.2. It tries to preserve brightness differences.
2.4 relative will try to preserve gamma tracking (instead of brightnes separation), but knowing that your display cannot go to infinite contrast 0nit black.
Should I disable vcgt, as suggested before in this thread?
if you disable VCGT in LUT3D creation, it will assume that display without ICC VCGT calibration matches perfectly ICC TRC (“nominal gamma”). It may not be true, so if VCGT is not linear apply it. The suggestion was because before you attached the profie we did not know VCGT near black
What do you mean by “with such data”?
Profile has fake infinite contrast, the kind of display profile we use for ICC color management in browsers or Photoshop.
Sorry for my noob questions, I am here to learn.
Instead of judging desaturation from visual, try to measure the whole pipeline with LUT3D and madVR as render, since that idealized matrix curve with fake infinite contrast seems to match display behavior.
Maybe its a levels configuration in madVR, or some custom desaturation you applied, we cannot know.If it’s there, you should be able to measure it. Try to use ISO 12646:2008 since it has a lot of greys and will track also the near black boundaries of colorspace.
