Gnome 40 colormanagement broken?

Ah, this thread explains a lot. I thought it was Ubuntu.

But gnome is the reason for this bug.

I no longer have any problems with LMDE 5 / Cinnamon 5.6.7.

Wow, this explains why my colors are messed up since upgrading from ubuntu 20.04 to 22.04…
I even calibrated my screen with the latest version of DisplayCal based on python3 and a Spyder 5 since upgrading ubuntu 22.04.
So according to @Romano_Giannetti the key is getting a valid icc profile out of DisplayCal?
But it seems that the used version of Argyll CMS (2.1.2) is an issue, although I didn’t encounter any error during the calibration process. I however will try to reproduce what @Romano_Giannetti suggested tomorrow.
Sorry for the stupid question, but should “Interactive display adjustment” be turned on or off now? :sweat_smile:

Using darktable-cmstest I always get an empty output:

XWAYLAND1	the X atom and colord returned the same profile
	X atom:	_ICC_PROFILE (0 bytes)
		description: (none)
	colord:	"(none)"
		description: (file not found)

Only when I go back to DisplayCal to install the profile for all users, darktable-cmstest is able to discover the profile:

XWAYLAND1	the X atom and colord returned different profiles
	X atom:	_ICC_PROFILE (968540 bytes)
		description: DELL U2410 2023-01-14 S XYZLUT+MTX
	colord:	"(none)"
		description: (file not found)

Is there also a general problem with wayland? Did anybody get it working with wayland, or do I have to switch back to xorg?

I had to leave that unchecked. If you check that, DisplayCal tries to guide you to change the color setup of the monitor, and for me it ended with a very greenish thing that was impossible to calibrate. But probably it was my fault — I really struggled to find/understand the information.

Never tried to use that with wayland. I had so many things working funny or not working that I decided that that was a fight for another time :wink:

By going back in this discussion I learned that wayland does not (yet) support color management and this was exactly my problem. Once I switched back to xorg color management seem to work again.

After sorting out this problem with wayland I’m kinda struggling similiarily to get decent fresh color calibration with DisplayCal.
Turning off “Interactive display adjustment” definitely gave me a subjectively better looking display color profile than leaving it on and trying to follow the initial color & brightness adaptation process with the monitor controls.
I’ll further tinker around with that and will get back once I found a satisfactory outcome :crossed_fingers:

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Just as a demonstration of what @Romano_Giannetti already struggled with when having the “Interactive display adjustment" turned on: in my previous calibration run I made sure to balance out the colors as DisplayCal asked me to, using my monitor controls. And when I apply the new display color profile and start another calibration run I end up with this starting point:


What the heck is going on here? Now the green gain is way to high and I need to correct it in the monitor settings again, and at the same time pull up the red and blue gains.
My expectation would be that my starting point would be the same as in the previous run.
Can anybody explain what is going on here?

Edit: after I reverted the current display color profile to the one I had selected before the 1st run I got the same result in this “interactive display adjustment” dialog. So I think it is always a good idea to revert back your current display color profile to a neutral / automatic one, or turn it off completely before starting calibration runs. I’ll try another time by turning color management off during calibration.

Hello, did you choose on the main screen of DisplayCal under Settings your previous calibration?

I didn’t use DisplayCal to set the display profile, I always use the gnome-control-center color dialog.
And I even noticed that DisplayCal is smart enough to detect that there is an active display profile set and immediately disables it once the calibration started. So I really don’t know why it sometimes works and sometimes not.

But coming back to my overall display calibration issues:
I finally managed to get a decent display profile with DisplayCal, it took me some hours of reading several forums to understand why my Dell U2410 wide-gamut monitor is kind of special and needs additional steps to get a decent calibration.
Here are my gotchas:

  • The monitor offers several color presets:
    • Standard (uses the full wide-gamut capabilities)
    • sRGB (clips gamut at sRGB boundaries)
    • Adobe RGB (clips gamut at Adobe RGB boundaries)
    • Custom (highly discouraged profile as it does some really nasty mappings)
    • and others like cold / warm / gaming etc.
  • My biggest mistake was, that I was using the custom mode, as this one allows adjusting RGB gains to set a decent white point before calibration starts (“Interactive display adjustment”)
  • I didn’t know that my colorimeter (spyder 5) is not very suitable to calibrate wide-gamut screens, spectrophotometers are better suited. However DisplayCal allows correction profiles, which are made using spectrophotometers. With those user-created profiles you’re even able to get a decent calibration with colorimeters. Those profiles are not only specific for the screen but also to the selected display color mode.
    I was lucky that people already contributed a bunch of those profiles to this database for my screen-colormode combination.
  • Next problem: color mode presets don’t allow tweaking RGB gains on my monitor, however there is a hidden factory calibration menu which allows to set RGB gains for all color mode presets. I chose the wide-gamut standard profile which equals 6500K.
  • I then started with fresh DisplayCal settings, by selecting the “Photo (D50, Gamma 2.2)” preset and changing the whitepoint to 6500K to match the monitor color mode preset
  • And voila, I got a decent ICC profile with subjectively accurate colors and so far I have not seen color banding in any of my “corner case” test-photos, which I encountered with previous profiles
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Yeah, color management fun! :wink:

I made several monitor profiles in the last 10 days with Argyll and DisplayCal, just to re-calibrate my screen. That is a Nec MultiSync (not wide-gamut) and I used a X-Rite i1 Studio (a photospectrometer).

Some of these profiles were nearly identical, while others showed the colors in a (sligthly) different way. I then installed the profile that I thought was “good”. But after two days I thought, hey, that one is too saturated!

Which made me pose the question: what is a good monitor profile? How can I know, apart from judging with my own eyes, if the whites are coolish or warmish or neutral? Or: what is a neutral white or gray?

In the end I did another calibration. I set my monitor to Custom 5000K and used the DisplayCal profile called Photo D5000 and gamma 2.2, highest quality possible. I ended up with a profile that seems to be “correct” (whatever that word means in this context).

As I said: CM fun! :wink:

The flatpack of DisplayCAL has been updated to ArgyllCMS 2.3.1 and so it stopped to work, again.

You need to downgrade it:

sudo flatpak update --commit=3f9ba184d56baa44cd579c171ce05aa344bf9fbd11e0857aba3c153ff1108266 net.displaycal.DisplayCAL

and then it seems to work again. Grrrrrrrrr…

Have you tried to clone the forked DisplayCAL repo and start it from there?
Following those steps to make sure all dependencies are locally installed:

At least the last time (like 6 months ago?) I started it from the cloned repo worked for me well.

IMHO, a “good monitor profile” can only be judged by a profile verification run under various conditions, like different time of day, desk lights on/off. If the values are still close enough I’d say it should be fairly accurate.

But knowing myself how subjective this subject matter is, I started to pick images from my portfolio with tricky / saturated colors and compared them with the display profiles in question. It turned out that some profiles which looked subjectively good (meaning neutral) suddenly had problems rendering some colors and created weird color artifacts. As a very rough “sanity check” sometimes it also helps to compare those images side-by-side with other displays like smartphone or laptop. If only your monitor with the recent monitor profile is the outlier, maybe it’s crap.

Just as an update from my side: I replaced my 11 year old Dell U2410 monitor with a new BenQ PD3420Q 34" 21:9 ultrawide as it became almost impossible for me to get satisfactory calibration results. Maybe the panel already degenerated too much.
I was contemplating on a two monitor setup for more virtual real estate, after I also have such a setup at work. But keeping two monitors calibrated and showing exactly the same colors would probably drive me nuts, hence going for an ultrawide aspect ratio. I’m happily using the build-in factory-calibrated sRGB mode, which looks very neutral and pleasing so far. So no need to create a monitor profile so far.