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post #1 of 6 Old 05-25-2020, 05:14 AM - Thread Starter
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Monitor calibration

Having some issues with the black floor on a AOC Q3279VWF.

With an 100% black background (other other tools) the black floor is elevated. The monitor has something called DCB/Dynamic Colour Boost which lowers it. Also has a Demo function with only half the screen showing the changes.
It also has a color temperature modes, with sRGB lowering the black floor even more.

When using brightness calibration pattern sRGB crushes everything below the 23 bar. In the Disney disc pattern the 3% star is barely visible.

The problem is I don't know how to get the low black floor without getting crushed blacks.

I've set to color temperature to User (50/49/49), DCB to Auto, gamma to 3 (2.1), brightness to 68, and loaded the ICC profile as indicated in this review: https://pcmonitors.info/reviews/aoc-q3279vwf/
Also tried the ICC profile from the manufacturer.

The review states that sRGB also has 2.1 gamma, so how does it achieve lower a black floor?

RGB Full from NVCP. The monitor does not seem to have a Limited option.

The black floor is still higher than sRGB. When selecting sRGB the most display settings are not available.


How can the black floor be lowered without getting black crush?


When testing the patterns no matter what the Brightness setting was selected from the monitor there was no black crush, except for sRGB. The image dimmed or brightened, but the 16 bar was always visible. With the Contrast pattern it behaved normally, increasing Contrast from the monitor blanked out the bars from 235 downwards.


With the calibration tools in Windows in order for the Gamma pattern to look as in the example, the slider had to be moved upwards. The pattern looked better, but the image because washed out.
Are the Windows calibration tools ok to use?


LE:
Will a colorimeter with a lut, especially for madvr fix this issue?

LE2:
The monitor also appears to enhance banding posterization vs. the other displays. It's particularly bad in darker scenes.

Last edited by noob00224; 05-25-2020 at 06:11 AM.
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post #2 of 6 Old 05-25-2020, 10:14 AM
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You should set the color temperature setting in your Monitor to Warm. Disable DCB and DCR too. And then set Brightness and Contrast using Pluge patterns/clips.

If you get a probe, it should be possible to create a calibration 3DLUT for use in madVR, if your monitor is well behaved after the above setting changes.
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post #3 of 6 Old 05-25-2020, 11:28 AM - Thread Starter
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Quote:
Originally Posted by omarank View Post
You should set the color temperature setting in your Monitor to Warm. Disable DCB and DCR too. And then set Brightness and Contrast using Pluge patterns/clips.

If you get a probe, it should be possible to create a calibration 3DLUT for use in madVR, if your monitor is well behaved after the above setting changes.
What I'm trying to accomplish is to get the lowest black floor. Warm raises the black floor. I don't use DCR. DCB and sRGB lower the black floor. DCB is not an issue, the issue is that sRGB crushes blacks.

As I wrote in the first post changing the Brightness from the monitor does not reveal or hide the pluge black level bars.
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post #4 of 6 Old 05-25-2020, 12:08 PM
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If sRGB crushes black and raising the Brightness setting doesn't fix that, you should not be using it. Try the other presets and find the one which gives the lowest black without clipping.
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post #5 of 6 Old 05-25-2020, 12:50 PM - Thread Starter
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Quote:
Originally Posted by omarank View Post
If sRGB crushes black and raising the Brightness setting doesn't fix that, you should not be using it. Try the other presets and find the one which gives the lowest black without clipping.
That's just it, with sRGB the Brightness setting is locked.

There should be no reason why the floor could not be lower and the blacks not crushed. I know the only way to fix this would be via a lut, but I wanted to know why this is happening.
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post #6 of 6 Old 05-25-2020, 01:21 PM
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If you must use the sRGB preset with clipped black levels, one solution is that you load a 1DLUT in the GPU (VCGT) which carefully raises black only enough to get past the clipped levels. But I guess you may have to take professional help in creating such a VCGT.

For madVR usage, there is an easy solution. You use custom output levels and increase the lower threshold such that you get past the clipped levels. So, let's say you find the threshold to be level 3, then in madVR you will set the custom output levels as 3 to 255.
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Last edited by omarank; 05-26-2020 at 03:14 AM.
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