HDR image creation, creates a purple image

[DixFlatline]

Describe the bug

I have a Canon IXUS camera, that is hacked wuth CHDK to save RAW images in DNG format. Working very fine so far with Darktable.
But when I try to create a HDR image (yes, CHDK hack allows HDR script to export 3 RAW images for HDR), the resulting image is a purple image. Like grayscale, but all purple tones. DT creates it, doesn't complain, I can open it... It's just purple, not fine.

The images I tried with, were totally unprocessed, as they came out of the camera.

Steps to reproduce

Click on the 3 Images to use for HDR.
On right panel, click on create HDR.
See result image, all purple tones in my case.

Expected behavior

Create a HDR image properly.

Logfile | Screenshot | Screencast

No response

Commit

No response

Where did you install darktable from?

flatpak

darktable version

4.4.0

What OS are you using?

Linux

What is the version of your OS?

Ubuntu 20.04 LTS

Describe your system?

No response

Are you using OpenCL GPU in darktable?

None

If yes, what is the GPU card and driver?

No response

Please provide additional context if applicable. You can attach files too, but might need to rename to .txt or .zip

No response

[ralfbrown]

My guess is that either the raw black point is off, or the white balance coefficients stored in the file.
It will be a lot easier to debug with actual images exhibiting the problem.

[DixFlatline]

I uploaded an image when I put the issue but it seems it didn't finally get it.
I'm gonna try to send 3 RAWS + Final image. Is that possible?

[DixFlatline]

Hi again.
I uploaded the 3 RAW images plus the HDR produced by DT ( + JPG as reference) here:
https://mega.nz/folder/BzVB0LzT#-iuEcS9QK9KDTSP5S_6_AQ

I hope it helps.

[github-actions]

This issue has been marked as stale due to inactivity for the last 60 days. It will be automatically closed in 300 days if no update occurs. Please check if the master branch has fixed it and report again or close the issue.

[kmilos]

@DixFlatline The link seems to no longer be active...

[github-actions]

This issue has been marked as stale due to inactivity for the last 60 days. It will be automatically closed in 300 days if no update occurs. Please check if the master branch has fixed it and report again or close the issue.

[kmilos]

Maybe similar to darktable-org/rawspeed#716?