@andy_t Something wasn’t sitting right with me, I thought we had done something about the color rendition of the 90D before. And it turns out, I was right. I just hadn’t looked for it in the right place. We have had a high-quality DCP profile available in the development version of RT since the end of August 2020: Improved Canon EOS 90D dual-illuminant DCP · Beep6581/RawTherapee@8a4d12c · GitHub
The caveat is that this does not work on CR3 files, because their metadata cannot be read (yet), so they cannot be recognized. Conversion to DNG first will pick up the DCP profile automatically in RT.
You have to use a nightly build from here Release Automated Builds · Beep6581/RawTherapee · GitHub
@ggbutcher Your derived color matrix is quite a bit different from the one in LibRaw. When I apply them to the same image, I get noticeable differences, especially in some colors (pesky blues). See here:
LibRaw matrix
Butcher matrix
I tend to like the LibRaw version a little more, but I wouldn’t expect that much of a difference tbh.