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Hi everyone!
I load 3D LUTs generated using DisplayCal and i1Display Pro colorimeter with my displays in DWMLUT. Everything is perfect. I don’t want lifted shadows, that happen when display is forced to have sRGB transfer function. This is the case with using ICC profiles and apps like Photoshop. By using DWMLUT my displays are calibrated to Gamma 2.2 (also 2.4, 2.6 and 1886). It is system-wide and I like it. But I can’t update to 24H2, because DWMLUT isn’t working there.
I’ve read here about MHC2, that it may help with this, when using ICC profiles (callibrated or synthetic? 3d tables or matrix only?).
I’ve read on MHC2 github repo something about issues with bit depth. Also something about linear interpolation between gamma points (why it is called gamma then, if there are points? And lerp sounds not smooth, if I get it right).My qestion is what is the current state? Is it possible to get system-wide calibrated SDR rec709(sRGB) gamut 2.2 gamma display on Windows 11 24H2? NOT sRGB EOTF. Not to start sRGB vs pure gamma holy war, my main app is DaVinci Resolve, so pure gamma only.
If it is possible, how is it in terms of quality?
Also, I’m not sure I understand the whole image path now.
An app sends some data, that is, lte’s say, assumed to be a display reffered sRGB gamut sRGB curve encoded image. Color management system is told by ICC profile that the display is also sRGB sRGB, so in the end it leaves the image unchanged. If I create ICC profile from characterisation data, ICC profile knows now that the display is actually Gamma 2.2. In this case color management system lifts shadows to make the display to perform as sRGB, since it thinks that if the image is encoded with sRGB it should be decoded the same way. But I don’t need that. I need whatever pixel my app sends, to be decoded using gamma 2.2 display EOTF. So, if I get it right, MHC2 somewhow tricks the system and forces it to do what I want. Not at all understand what it does (I can come up with at least one way it might do it). But does it do it?
Or currently it’s better for me to stick to previous Windows version and keep using DWMLUT?
Thanks!Calibrite Display Pro HL on Amazon
Disclosure: As an Amazon Associate I earn from qualifying purchases.Your profile probably contains a VCGT tag (view using Profile Info -> Calibration curves) consisting of 3x1D curves which map your displays native response to the gamma of your choosing (say 2.2). This information is loaded by the graphics card and applied to the whole desktop.
Color managed apps like Photoshop don’t read VCGT, they may read a different tag called TRC.
Thus, if you provide a TRC with sRGB encoding, or maybe even drop the TRC tag completely, Photoshop will not know that your display is actually showing 2.2 gamma and won’t map sRGB encoding to it.
