darktable-org / darktable-org/rawspeed
Kodak DCS 520c, issues with ISO
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- Dominant language
- C++
- Stars
- 456
- Forks
- 147
- PR merge metrics
- No merged PRs in 30d
Description
This camera is when shooting in raw truly ISO less. ISO 200 or ISO 1600 are just the same.
DCS 520c saves raw files in .TIF but darktable can't read those. Replacing .TIF with .DCR is a workaround.
Now the problem. darktable shows major sensor clipping in the raw file at ISO 1600. It should be identical to the raw file at ISO 200.
Raw files and how RawTherapee works without sensor clipping
https://discuss.pixls.us/t/darktable-increases-brightness-in-raw-file-with-no-way-back/27306
OS: Ubuntu 20.04
darktable 3.6.1
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by reproducing the report with the Kodak DCS 520c raw files, comparing ISO 200 and ISO 1600 behavior and the .TIF/.DCR workaround in darktable 3.6.1 on Ubuntu 20.04. Then locate the camera's raw decoding path in the rawspeed C++ code; done means the ISO 1600 file no longer shows the reported sensor clipping and remains readable.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- computer-vision
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100