Currently evaluating highlights reconstruction for linear raw / sraw files.
As these are not common, please provide sample files, optimally strongly blown out parts like sky with clouds.
3 Likes
I have an S-Raw setting on my Canon 5D4, and also M-Raw. As I think I read about wrong white point issue in particular with .arw files, but not exclusively, are you interested in samples from Canon?
6D mRAW and sRAW ISO 100 and ISO 800. CC0
20221011_MG_9669.CR2 (15.8 MB)
20221011_MG_9670.CR2 (10.3 MB)
20221011_MG_9674.CR2 (20.0 MB)
20221011_MG_9675.CR2 (13.2 MB)
@hannoschwalm Are you also interested in linear DNG files?
In that case linear DNG file can be created using Adobe DNG Converter from any other real raw file by enabling an option and they’ll retain the blown out highlights:
- Click Change Preferences.
- Choose Compatibility to Custom…
- Enable `Linear (demosaiced). Keep Backward Version to DNG 1.6.
(P.S. I just noticed that currently the black levels are wrong and must be changed by hand in the raw black/white point darktable module, this will require a fix for rawspeed probably similar to the one I did for rawtherapee: dcraw: use the right black levels for linear DNGs by sgotti · Pull Request #6444 · Beep6581/RawTherapee · GitHub)
If those linear dng are out-of-camera, yes I would be interested. Otherwise no.
Canon 5D4 samples, ISO 100 and 3200, just tell me if you need more …
20221637-100.CR2 (31.7 MB)
20221638-100-m.CR2 (21.4 MB)
20221639-100-s.CR2 (13.9 MB)
20221640-3200.CR2 (39.0 MB)
20221642-3200-m.CR2 (29.8 MB)
20221643-3200-s.CR2 (19.5 MB)
Is it an indicator of wrong white point that raw overexposure indicator does not work for the m- and s-raw?
You also want linear DNG coming from other tools ?
If so , point out play raw files you think are good candidates, and I’ll whip them up.
No.
But what is then the reason? It works for the regular raw but not for the m or s reduced resolution (the regular raw is available along the other samples in my post) …
The algo is wrong 
I will fix it.
1 Like
Fujifilm X-H1 samples
_DSF5778.RAF (48.2 MB)
_DSF5829.RAF (48.1 MB)
_DSF2439.RAF (48.2 MB)
These files are licensed Creative Commons, By-Attribution, Share-Alike.
Note: Are regular RAW but may be great to test your highlight recover method.
One of them is a challenge 
1 Like
Keep uploading sraw files with blown highlights please!
I definitely need more files for proper testing, algorithms seems to work as expected but without full confidence there will be no code landing in dt.
Maybe another question. What are ‘linear sraw’ files ?
A compression format used by canon ? Why ‘linear’ ? Is it already demosaiced in camera to store the file as a different resolution or something?
It means the rgb data are already linear - or you could say already demosaiced. But they are not yet corrected for white balance.
I think fixes for these files will hopefully fix linear DNG HLR as well…
I think and hope so. Since @hannoschwalm only wants out of camera and not linear DNG generated by other tools I’ll wait for his PR and test some of them.
1 Like
If you have proper files generated otherwise, go ahead. (there have been so many crappy dng files presented in issues I feared to get “spammed”
DSC_4287_dxo6.dng (60.7 MB)
From Blowing steam and highlights :-)
20120116_D7K0879 (1)_dxo6.dng (57.7 MB)
From old dubai skyline (and highlights reconstruct in filmic)
Feel free to label them as unusable for you. That means my problems with linear DNG and HLR are unrelated to what you are working on .
These are DNGs that otherwise load and work fine. I can also export them in a way that the writing program does its own HLR, and then I’m perfectly happy with them. But I’m guessing the data doesn’t truly ‘stay linear’ then (have to lower exposure in DxO before export) and while DxOs HLR is working, it’s not the best in any way.
I’ve done as little as possible to the files. Should be pretty much as close to the original raw as possible, but demosaiced and rescaled to be between 0 and 65535 (so DxO interprets the black and white levels of the source raw file).
Pick one, or all, or none… all up to you!
1 Like
(This file keeps saying there is an upload error. To big? (Over 100mb).
From To the Skies - Strange behaviour in highlights