BUG: CR3/DNG/tiff files silently fall back to jpeg/8bit demosaicing
What happened?
I have a Canon .CR3 raw image taken on a Canon R6 mk1 with an EF f/1.2 50mm with over- and underexposed parts in the image. The exposure range shouldn't be anything crazy that a raw image shouldn't be able to handle. What I see happening is clipping in the light and dark areas that I can't restore by adjusting exposure or other sliders. A tool such as Geeqie doesn't show the clipping, suggesting the issue lies in the way that RapidRaw demosaics the image.
Some research with an LLM hints that while Geeqie uses libraw / exiv2 (C++), RapidRaw uses dnglab (Rust). The LLM also suggested to convert to dng and try again as a work around, but I haven't tried that yet.
The editor works fine, but it is only able to edit the images as if they were jpg, meaning that big exposure adjustments don't work great and color correction isn't as good.
Incidentally, I have noticed that loading images sometimes "freezes": I see a spinner for loading the .cr3 file, but it never completes. I wondered if this was connected somehow... as in dnglab not being able to read the file?
What did you expect to happen?
I expected the images to be edited as a regular raw image, with a high amount of control over detail recovery.
How can we reproduce this?
Best way to reproduce this is by using a .cr3 file with clipping. I have attached it as a .zip folder with a single picture in it.
Operating System
Other Linux
RapidRAW Version
v1.6.3
Additional information
At this point, I have too little experience/understanding of the underlying tools to judge if the issue comes from RapidRaw or from dnglab, and how this impacts where to raise this bug report. CR3 should be supported by dnglab, according to their page... but even if there was an issue there, I'm not sure how I would raise a bug report there relating to RapidRaw, but maybe we can figure that out together if this gets picked up.
As a total side remark: this tool is really fantastic. I am super exited about this project. Even though my experience is close to zero, I want to try and see if I can build from source, perhaps that will also help me understand what is going wrong here. Regardless of that I just wanted to say thanks for making/starting such a fantastic tool.
Acknowledgement
- I have verified that my camera and lenses are supported by the external libraries listed above, or my issue is unrelated to camera/lens support.
- I have searched all existing issues, both open and closed, and did not find a duplicate.
Source: CyberTimon/RapidRAW