I test 8k+ and when I use the desktop mode, I found that the white color is too bright.
I try to decrease the backlight to be 0 and not help, so I decrease the contrast and brightness.
But I feel that the black color is better, so I try the affeted the manor. A game which always has issue about black color because it look you can see the grey fog over the game environment.
When I test, wow this is better. And I think the backlight at 0 and contrast, brightness at default is okay.
So I am not sure that this happened in 8k+ only or not, so I try to test 5k+ and it get the same result.
I try to use the backlight at default and get the grey fog effect.
So the wrong calibrate backlight make the 5k+ to has issue for a long time. Another game which has the same result is Titanic VR.