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On a 700:1-1000:1 display trying to show 2.2 or 2.4 gamma about two near black greys are going to show almost equal or visually equal. Asume 100cd/m2 and do the maths.
Anyway, measure them. RGB 000, RGB 1 1 1, RGB 2 2 2, RGB 3 3 3 and let’s see if there is a crush or just very close values.Maybe banding is a better descriptor than crushing? See attachments. One is from my monitor that has no problem with calibration, one is from the one with problems. And the one with problems should have far better colors.
Another example since I can’t edit the post above. You can see that the black tones are distinct, but the are very far apart.
In the other example you can see his eye in the good one, but just squares in the bad one.
This can be caused by low quality monitor and should be present even disabling GPU calibration mosty non correctable,
or
can be caused by GPU calibration (low bitdepth + no dithering) on bad monitor (because it needs more correction), non corretable unless you try to enable dithering (read sticky thread for nvidias) or change GPU for other without those issues.
Both displays are 8 bit. My point is that the video compression is clearly visible on one monitor and not on the other because of the black values.
Both displays are 8 bit. My point is that the video compression is clearly visible on one monitor and not on the other because of the black values.
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This can be caused by low quality monitor and should be present even disabling GPU calibration, mosty non correctable,
or
can be caused by GPU calibration (low bitdepth + no dithering) on bad monitor (because it needs more correction), non corretable unless you try to enable dithering (read sticky thread for nvidias) or change GPU for other without those issues.
It does not matter if link between GPU and display is limitd to 8bit.
Do you get the same results with Datacolor’s calibration app?
The results with the SpyderX software seem comparable.
SpyderX Pro on Amazon
Disclosure: As an Amazon Associate I earn from qualifying purchases.Have you changed videocard together with display? Profiles usually breaks gradients. This happens in two stage: by videocard with rough calibration (linearization) curves correction (these are loaded to videocard, you flashed them when chose “reset”), and by rough CMS work (like Ps does, but Lr not). AMD only implemets vcgt correction well (use full driver), some NVidia cards can do it with some hack, but NVidia ignores user complaints for unknown reason. Try to change curves bit depth in Profile Loader drop down menu. The third chain link is your display innterface, internal bit depth and panel bit depth.
P.S. There’s well known problem of different gamma for video. Rec.709 has 2.4 gamma (high contrast “in numbers”, more detailed dark area), while consumer displays usually have gamma near 2.2 and sRGB has linear (=1) gamma in dark area. The problem is also depends on your movie player, it may or may not support track and display profile gamma. Movie player may be incompatible with XYZLUT profiles, try to use simplistic 1xCurve. You can also try to set gamma 2.4 in display menu and calibrate display for 2.4.
