System profile is generally your monitors (hopefully calibrated) ICC profile. Your workinf profile is separate and different profile.
I get that, and yes, the .icc profile is generated by DisplayCAL, following calibration. But you’re not answering my question.
Why doesn’t RT show the same image GIMP does when they’re both using the same .icc profile?
I don’t think you’ve given us enough information to adequately answer that question, hence the lack of answers.
You’d need to detail all the ICC profiles in your workflow for each application. If they’re all 100% the same and you load the same tiff into both RT and GIMP, then they should display the same.
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There are no “all profiles”. I use a single .icc profile in my workflow. I install it as a system profile and just enable “use main system profile” in all apps.
But… In RT I load a raw and in GIMP I load the tiff RT exports… Shouldn’t they still display the same? They used to, for the longest time…
If your Working profile is your systems’ calibrated monitor profile, that is not optimal.
Generally there are several profiles at work: input, working, display, and output.
You misunderstood, likely due to bad wording on my side.
My working profile is ProPhoto, display is the calibrated system profile from DisplayCal, output is sRGB and input… I’m not sure and I’m not at the computer right now.
Most probably it’s your camera profile (or the profile your input is encoded in, when editing JPG/TIFF/PNG and so on).
Oh yeah, I think this is set to auto.
Not necessarily:
What you see in RT is input → working → display profile.
What you see in GIMP is (input → working → export) → display.
Depending on the gamut of the export profile (e.g. much smaller than display one) and the mapping done by the CMS (perceptual, relative, etc.), you can get different looking images.
Hence the soft-proofing.
As I already mentioned, screen profiles can contain several different data. What kind of profile type did you choose while profiling with displaycal?
I tried both an xyx lut + matrix and curve + matrix. As far as my issue goes, there is no difference between the two.
Are the two renditions slightly different or wildly different?
They’re not wildly different, but quite noticeably so.
The one in RT is more vivid and saturated than the one in GIMP.
I just realised something and I suspect that might be the issued, although I don’t really understand why.
Apparently, a lot of these yellows, perhaps all those that all apps but RT fail to display are out of gamut.
maybe try lut only (without matrix), I think that’s possible, or the simplest profile single gamma + matrix.
might also be a rendering intent issue
Again:
“Depending on the gamut of the export profile (e.g. much smaller than display one) and the mapping done by the CMS (perceptual, relative, etc.), you can get different looking images.”
As an experiment, try exporting to a larger gamut, e.g. Rec2020 w/ 16 bits. And then, as @paperdigits says, experiment w/ rendering intent (gamut mapping).
As soon as you export those out of gamut colors to e.g. sRGB, that data is irreversibly lost (either clipped or squeezed/compressed depending on rendering intent), and cannot be brought back even if your display can do better.
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Ok. The bug that I found about a year ago in Gnome is fixed.
However, the issue that is the topic of this thread quite simply seems to be related to the fact that there are more colors in the raw file when viewed with a tool like RT or dt, whereas in GIMP you can only open a demosaiced photo, and if that was saved in srgb one part of the colors is gone.
This is the conclusion I came to as well. Which just about puts an end to this conundrum. The issue is a non-issue, frankly just a lack of understanding on my part regarding how colour works.
Thank you to all of you that have offered their opinions, I think we can safely assume much to learn I still have.
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Fwiw, I always found this choice of bypassing the output profile in the preview puzzling. I do not understand what benefit it is supposed to give, and it’s one of the things I’ve changed for my own purposes.
In rawproc I can turn off the output profile by setting display.cms to 0. I use it occasionally to demonstrate things like the effect of color transforms without the interference of the TRC. But yes, doesn’t make sense for regular use.