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Hi,
Sorry for the stupid question, I am new to monitor calibration. I tried searching and I couldn’t find a related post.
What is the meaning of consistently high deltaE? It is usually around 3-4, and I’ve created a profile twice with similar results. I am using a Spyder 5 Express on Linux. I’ve attached a picture of the Profile Information.
Is it just a limitation of the panel?
Thanks.
Here is the output from the verification. Please let me know if there is a good result. Thanks again
Hi,
that is an OK result for a single curve + matrix profile. For a more accurate result, use XYZ LUT + matrix (the default) with 175 patches.
Hi Florian,
Thanks for the reply. I read on some tutorial that you have to use single curve + matrix if you want the ICC to apply to every program, even if it doesn’t support ICC profiles. Is that true? If so, what are the limitations of XYZ LUT + matrix? I am using X11 on Linux with KDE Plasma 5, if it matters.
Here are the relevant lines from the tutorial:
The Profile Type dictates the internal structure of the profile. There are two types of profiles: Matrix and LUT.
LUT Profiles are more accurate than Matrix profiles, but not compatible with every application.
To achieve an equal color profile throughout all of the applications that you use, and profile all applications are able to process, we will choose Single curve + matrix.
Thanks.
Thanks for the reply. I read on some tutorial that you have to use single curve + matrix if you want the ICC to apply to every program, even if it doesn’t support ICC profiles. Is that true?
No, that’s completely false. A program needs to specifically support ICC color management to make use of any ICC profiles. The only part that will benefit the whole system is the 1D calibration (videoLUT adjustment) that can be embedded in any type of profile, but that can only correct whitepoint and grayscale.
If so, what are the limitations of XYZ LUT + matrix? I am using X11 on Linux with KDE Plasma 5, if it matters.
Some color managed applications may not be able to use the cLUT part of cLUT + matrix profiles, which means they’ll fall back to the matrix (which in turn means the results you will get with these applications are identical to those with a curves + matrix profile, i.e. less accurate). That is the only “limitation” (which is not a limitation generally, and in addition under Linux, the only color managed programs that cannot use the cLUT of these types of profiles are WebKit based browsers such as Google Chrome. All other color managed applications under Linux use littleCMS, a state of the art color management module with support for all available profile types).
LUT Profiles are more accurate than Matrix profiles, but not compatible with every application.
That’s not quite correct: As mentioned above, those color managed programs will fall back to the curves + matrix part of the cLUT-based profile. And non color managed applications will not use any profile to begin with.
To achieve an equal color profile throughout all of the applications that you use, and profile all applications are able to process, we will choose Single curve + matrix.
The problem with this approach is that todays consumer displays are often not adequately characterized by a curves + matrix profile, because they have nonlinearities that cannot be expressed in a simple 3×3 matrix.
Thank you for the detailed reply. Is cLUT + matrix equal to XYZ LUT + matrix? If so, just to confirm, I should use XYZ LUT + matrix, and in the worst case it will fall back to the same quality as single curve + matrix, and it even having to fall back is rare on Linux?
Also finally, is there a way I can verify that the calibration is active on Linux? I am on Gentoo so I may not have installed the program that DisplayCal may expect to load the calibration after I select Install for current user. I do see a difference when I check/uncheck Preview, but I want to confirm it persists after reboot.
Sorry for the dumb questions.
Thanks again
Is cLUT + matrix equal to XYZ LUT + matrix?
cLUT is shothand for color lookup table. XYZ LUT falls in that category.
If so, just to confirm, I should use XYZ LUT + matrix, and in the worst case it will fall back to the same quality as single curve + matrix, and it even having to fall back is rare on Linux?
Yes, that basically the TLDR version of what I said above.
Also finally, is there a way I can verify that the calibration is active on Linux?
DisplayCAL installs an autostart entry, and logs to ~/.share/DisplayCAL/logs/DisplayCAL-apply-profiles.log
As another final few questions, the KDE Compositor, KWin, removed support for color correction because it was unmaintained. I can still select an ICC profile per monitor in Kolor-Manager(called Color Management in system settings), but I don’t know if it has any effect. Do you know if this is required if I install the profile with DisplayCal? Do I need any configuration to make littleCMS work in all my applications, or do they need to support it? Also, I had to install Oyranos to install Kolor-Manager, does it do anything since DisplayCal uses Argyllcms?
Thanks
As another final few questions, the KDE Compositor, KWin, removed support for color correction because it was unmaintained.
I think that relates to the KWin plugin that provided desktop-wide color management even for unaware applications. This is not required for color managed applications, but would have been nice in general.
I can still select an ICC profile per monitor in Kolor-Manager(called Color Management in system settings), but I don’t know if it has any effect
You can assign one of the test profiles located at /usr/share/DisplayCAL/tests and see if the embedded calibration is loaded.
Do I need any configuration to make littleCMS work in all my applications, or do they need to support it?
Some applications may need enabling color management in their settings. Some provide a checkbox “use system profile” (e.g. Gimp) and what they really mean is that they will then use the assigned display profile without having to specify the path in the application itself.
Also, I had to install Oyranos to install Kolor-Manager, does it do anything since DisplayCal uses Argyllcms?
It’s nice to have a graphical interface to manage profile associations.
Thanks. I attached the latest calibration, it seems much better (it’s a different monitor than before but they both had similar deltaE).
And actually finally, should I select Create 3D LUT after profiling, or is it unnecessary for XYZ LUT + Matrix?
Also, how do aware applications deal with multimonitor setups? For example, Firefox is aware to my knowledge. If I move the active window to another monitor, does it switch to the calibration from that monitor?
And actually finally, should I select Create 3D LUT after profiling, or is it unnecessary for XYZ LUT + Matrix?
3D LUTs are used by video editing/grading software as they typically don’t have ICC support.
Also, how do aware applications deal with multimonitor setups?
Many unfortunately don’t – Firefox is an example (it always uses the profile of the primary monitor).
