Hi @agriggio - thanks! for checking the files. A couple days ago I did notice a problem when processing the “very yellow flower” raw file (not from the tiffs you uploaded to filebin.net, rather I processed the raw file using the GIMP plug-in).
Double-checking today, I updated rawtherapee tthis morning, still on the floating point branch, recompiled, and opened the yellow flower raw file from within GIMP-2.9. I used the custom camera input profile (that’s in the zip file with the raw files) for my old Canon 400D as the input profile and also the output profile.
The image was transferred to GIMP without any problems, and still in the camera input profile color space, which is what I wanted. The blue channel is just right, still has all the original blue channel detail. But the red channel is clipped over substantial parts of the image:
In the original raw file there is a tiny spattering of clipped pixels in the green channel, but no pixels are clipped in the red channel. However, after applying the daylight white balance, a considerable portion of the red channel is driven to above 1.0 floating point. Figure 4 in this article shows the clipped green pixels: https://ninedegreesbelow.com/bug-reports/ufraw-highlights.html, and Figure 2 shows a similar-to-RT pattern of clipped pixels in the red channel. The clipped pixels in UFRaw are from a lack of true exposure compensation - UFRaw clips before doing exposure compensation, but I don’t think this is what RT is doing, leastways I’ve never seen this problem in RT before.
For 16-bit output, I would set the raw exposure compensation to 0.5 or even 0.25, to avoid clipping the red channel. But for floating point output I’d expect these “above 1.0f” channel values to be brought along without clipping (what darktable and PhotoFlow do). Is there a setting in RawTherapee that I didn’t set correctly? Here’s the pp3 file:
090916-1718-109-1543.cr2.pp3 (10.5 KB)