f.lux doesn't work properly with dual monitors when both are calibrated and using different ICC profiles

[Ameisen]

Windows 10 Pro 21H1

On my system, I have two Asus PB278Qs connected via DisplayPort to an Nvidia GTX 1070.

I have them both color calibrated (using a colorimeter) separately, and both have different ICC profiles.

Now that they both have their own profiles instead of sharing the same generic PB278Q profile, f.lux only appears to apply to a single screen (the primary).

[herf]

Can you post f.lux options > driver info so we can see the details?

This sounds similar to a configuration we have here (which is working as it tends to always work here!)

[Ameisen]

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Driver info
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The information below is already on the clipboard. Paste to the f.lux forum or email us for help.

NVIDIA 30.0.14.7212: NVIDIA GeForce GTX 1070 (20210913)
NVIDIA 30.0.14.7212: NVIDIA GeForce GTX 970 (20210913)

ASUS PB278, 597 x 336mm, built 2014
Chromaticities: 
  R=0.666016 0.330078
  G=0.309570 0.629883
  B=0.150391 0.040039
  W=0.313477 0.329102
  sRGB gamut: 99%, AdobeRGB gamut: 69%

ASUS PB278, 597 x 336mm, built 2014
Chromaticities: 
  R=0.666016 0.330078
  G=0.309570 0.629883
  B=0.150391 0.040039
  W=0.313477 0.329102
  sRGB gamut: 99%, AdobeRGB gamut: 69%

Unlimited gamma ramp=1, Internal ramp=1
Monitor 1 on NVIDIA GeForce GTX 1070
  Has VCGT profile=1, Gamma Ramp works=1
Monitor 2 on NVIDIA GeForce GTX 1070
  Has VCGT profile=1, Gamma Ramp works=1

Windows Build: 19043.1288

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OK   
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Color-wise, they both calibrated substantially differently, and are using two different ICC profiles.

[herf]

Okay we do know that NVIDIA has some settings in its own control panel that override color settings - can you check for "reference color" mode or something like that in the NVIDIA Control Panel? It should be turned off for f.lux to work.