I thought I’d managed to find a reliable workaround but further testing showed I hadn’t.
In some of my images, the red channel seems to being desaturated. At first I thought it was a colour profile issue but I’m not so certain now.
I have found that if I use the standalone DeNoise AI and use the Save As menu AND change the colour profile to something else, this happens:
Sometimes the image is not desaturated
The colour profile in the image NEVER changes.
For example, most of my photos have the ProPhoto RGB profile. If, when I save i DeNoise AI, I tell it to convert to sRGB, then on occasion (but not every time) the colours look OK. The image always always retains the ProPhoto RGB profile.
The desaturation only happens when the DeNoise AI engine is used. The AI Clear engine seems ok. I don’t know if the profile issues occur when using the AI Clear engine…
So, this could be a colour profile problem… But it might not be.