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As per the subject I’m trying to figure out what the right process is to calibrate with the driver srgb clamp on AMD. I see instructions for nvidia on the https://hub.displaycal.net/forums/topic/novideo_srgb-gpu-side-lut-matrix-lut-calibration/ but I want to double check if my process is correct.
#1
– calibrate monitor without clamp
– Edit the EDID, set the primaries to the measured ones using CRU
– Run a second calibration with the clamp enabled in driver
– Load second calibration with displaycal loaderor
#2
– Calibrate the monitor without clamp
– Just enable the srgb clamp to clamp it to srgb (Should I also edit the edid in this case?)
In this case, when there is srgb content with the clamp. Would the clamp essentially be applied twice and make the calibration incorrect?Or are both the methods wrong?
AMD sRGB clamp is like a “locked controls” novideosRGB app. You cannot choose white, gamma & colorspace, or destination colorspace (EDID).
Let’s assume a P3 display, D65, 2.2 gamma from an existing full native gamut display profile. Let’s assume that native gamut (EDID info) says P3 primaries, D65 , 2.2 gamma.
Appyling Amd sRGB clamp should preserve almost everything. Test with HCFR (be careful to configure near black settings & colorpsace & gamam set as reference)
Tesing in DisplaYCAL will be more complicated because it lacks of an option to “use some std profile as display reference, like srGB, but preserve current VCGT grey calibration). It is possible to validate it running a VM machine (sind DIsplaYCAL won’t clear VCGT in actual computer) or create a synth profile (sRGB-like) and then inject VCGT data in command line,… but it should be easier to do a test on HCFR.
(using this, all color managed apps will show wrong & desaturated colors, since display behavior with sRGB simulation won’t match display profile)Let’s assume that previous paragraph does not work (i’d bet that it works). Then as a solution enable AMD driver sRGB clamp, then profile as ususal. Resulting profile will have near sRGB primaries and it will valid if sRGB clamp is active.
(this works with color managed apps)Also remember that most color managed app only read display profile on app start, changing it will require app restart.
AMD sRGB clamp is like a “locked controls” novideosRGB app. You cannot choose white, gamma & colorspace, or destination colorspace (EDID).
Let’s assume a P3 display, D65, 2.2 gamma from an existing full native gamut display profile. Let’s assume that native gamut (EDID info) says P3 primaries, D65 , 2.2 gamma.
Appyling Amd sRGB clamp should preserve almost everything. Test with HCFR (be careful to configure near black settings & colorpsace & gamam set as reference)
Tesing in DisplaYCAL will be more complicated because it lacks of an option to “use some std profile as display reference, like srGB, but preserve current VCGT grey calibration). It is possible to validate it running a VM machine (sind DIsplaYCAL won’t clear VCGT in actual computer) or create a synth profile (sRGB-like) and then inject VCGT data in command line,… but it should be easier to do a test on HCFR.
(using this, all color managed apps will show wrong & desaturated colors, since display behavior with sRGB simulation won’t match display profile)Let’s assume that previous paragraph does not work (i’d bet that it works). Then as a solution enable AMD driver sRGB clamp, then profile as ususal. Resulting profile will have near sRGB primaries and it will valid if sRGB clamp is active.
(this works with color managed apps)Also remember that most color managed app only read display profile on app start, changing it will require app restart.
Correct me if I’m wrong. So basically what you’re saying is that with a native gamut display profile and then applying the srgb clamp. For all non color managed apps, the calibration should be preserved. However it will be wrong for color managed apps.
So the solution is to profile with the driver clamp on, and that profile will work everywhere.
IDNK what you want to do.
If you want to simulate sRGB for games and keep your native gamut, D65, 2.2 gamma profile eveywhere. Just enable sRGB simulation in AMD driver when you game. Disable after gaming. That’s all. Try verify with HCFR how good it is.ONLY if this does not work, calibrate & profile with sRGB simulation on.
