Thank you for your work and the result which is camera colour profile file.
It works perfect when manually loaded as a custom input profile, but I would like to make it automatic. Do you know how to do it?
I tried to rename file with the name of my camera - Canon EOS 250D and put it into dcpprofile directory in RawTherapee folder but it did not work. I made an alias in camera_model_aliases.json file in there but it also did not work.
I think that maybe it can be done as described in the RT official manual, to force software to read it automatically, but unfortunately I have no idea how to perform this operation in the file called camconst.json. I made an attempt just to check if it is going to work or crash the software. I copied that file to:
and tried to copy in this file the part for EOS 200D and rename it for EOS 250D, just for checking purpose whether or not software is going to take it and assign to photos from my camera. When all has been done, I run the RT and load to Editor mode some *.cr3 photo and something has happened because picture has been totally pink or totally white. When I deleted the file and run RT again, photos became normal.
Thus I think this could be the way, but how to take the info from *.icc file and put correctly to the camconst.json?
Maybe somebody else has some good experience with this issue?