Can I use this tool to properly calibrate an HDR display on Windows?

[justjanne]

I'm using a Dell UP2718Q display on Windows 11. I've successfully used my x-rite i1 Display Pro to calibrate the display in SDR mode.

I believe that Windows is applying the wrong gamma curve in HDR mode. In HDR mode both SDR and HDR content looks washed out.

ICC profiles created with DisplayCal in resolve mode using dogegen do not have any effect on this.

When I calibrate the display manually with AMD custom color settings and DisplayCal's "Start Measurement" mode with my i1 Display Pro, I can get SDR colors to look as they should and match my other displays. Using this I can also get HDR colors to match more closely.

From what I can tell, instead of using this (flawed) manual calibration, I should be able to achieve the same using DisplayCal and MHC2Gen.

What's the correct process for a) generating a profile in HDR mode and b) getting Windows to apply that profile correctly?

[dantmnf]

I believe that Windows is applying the wrong gamma curve in HDR mode

Windows uses the "technically correct" sRGB transfer function to convert SDR content to HDR10 (PQ-encoded absolute brightness, and technically impossible gamut).

Your display device is responsible to convert signal encoded in technically impossible range to something reasonable for the panel. We could adjust gamut mapping behavior with MHC2 matrix, but not brightness mapping since the red component on wire may contribute to green and blue on the panel.

Given SDR content always converted to HDR10 correctly, you can run DisplayCAL verification against sRGB profile to somehow check HDR mapping behavior.

To profile raw PQ mapping (input brightness to actual brightness), you can use dogegen and ArgyllCMS command-line tools.