Colors slightly off when opening Canon RAW file

vanekjar · July 24, 2019, 4:29am

Hi,

I wonder why the Canon RAW from 550D has a slightly green-ish tint when I open the file with no transformations applied (just base curve). Orange colors are shifted into yellow. In Lightroom and Ufraw it looks exactly the same as in generated JPG from camera.

Sharing original RAW file as well as exported JPGs from Darktable 2.6.2, Lighroom and Ufraw. In all cases camera white balance was used.

IMG_9526.CR2 (24.0 MB)

Darktable

Lightroom

Canon 550D JPG (Landscape picture style)

Ufraw

MStraeten · July 24, 2019, 5:37am

Lightroom applies some different settings. Best solution is creating a specific camera profile like described in PIXLS.US - Profiling a camera with darktable-chart.
Maybe a first step can be applying styles created for another canon cam - take a look at the canon dtstyles on https://dtstyle.net/.
There are several styles mimicing Canon presets for the m6 e.g. https://dtstyle.net/download.php/438/Canon_M6%20Standard.dtstyle. Maybe these can be used to achieve a better base for further editing.

vanekjar · July 24, 2019, 6:30am

Thank you for the explanation.

I am adding another case of the same issue, maybe even more visible.

IMG_9382.CR2 (29.6 MB)

Darktable

Lightroom

Canon 550D JPG (Landscape picture style)

Ufraw

pk5dark · July 24, 2019, 10:06am

basecurve already applies heavy “transformations”. LR does it even more. Some very general comments from a dt user:

Camera specific basecurves were provided by users and could not be proofen to be correct.
basecurve and the pixelpipeline of darktable is been discussed a lot over the last year, because of various flaws, but this is maybe unrelated to your issue
correct colors is something which none of any RAW developers will produce without some sort of calibration
most use the term of correct colors but they are talking about pleasant colors.
I hope your screen is calibrated and you have a color managed workflow.

gadolf · July 24, 2019, 10:45am

I get a similar result to LR by applying the following modules

filmic (with preserve colors ticked)

tone curve

EDIT: I feel like as if these steps “unveil” what goes behind the scenes in LR. As a side note, it’s amazing how far I had to go with extreme luminance saturation in filmic to get those dark yellows. I’ve never used it like this before. It really seems that we’re not talking about “correct colors”, but “pleasant colors”, as @pk5dark stated before. Better put, what Adobe thinks “pleasant colors” are.

Entropy512 · July 24, 2019, 11:40am

As a quick experiment, try either disabling the basecurve module or using a version of darktable that has @Edgardo_Hoszowski 's “Preserve Colors” improvements to basecurve. (Currently, only dev builds from git master will have this)

ggbutcher · July 24, 2019, 4:02pm

I worked your image in my hack software, where I could specifically control each transform to the raw data - firstoff, your camera’s raw file exposed some bugs in my color filter array logic, so thanks for the opportunity to fix those.

Summarily, I’d speculate the differences you’re seeing are in the camera color primaries used by each software: RT, for your camera, appears to use the dcraw values (inspection of camconst.json), where LR probably has its own primaries in a DCP profile. There are also some tone differences, so whatever basecurve each is applying is having some differential effect.

I have to run to work (benefits of part-time employment yet to be realized… ), but I’ll try to post an image or two later.

vanekjar · July 24, 2019, 5:17pm

I agree that LR produces pleasant colors that are not necessarily realistic. But honestly I think that is the output most of the users actually want, including me. Is there a way how to configure Darktable to produce similarly looking colors by default? I would like to avoid spending first 5 minutes with each picture just to get to “basic state” of balanced colors.

I also updated my post with in-camera JPGs for comparison.

paperdigits · July 24, 2019, 5:26pm

You should make a preset with your ~5 minute modules and auto apply the preset.

vanekjar · July 24, 2019, 11:07pm

I think it may be fairly easy to tune settings for single type of scene. But I am struggling to come up with general preset that would work for all types of photos and colors.

paperdigits · July 24, 2019, 11:37pm

For the way I expose and work, the preset for me would be Exposure +1 and Filmic with the ~12ev preset.

Celsus · July 27, 2019, 7:57am

@vanekjar As a quick hack you can use the Canon M100 Faithful icc from here: Canon M100 icc Profiles for Darktable, made from DPP output - #2 by afre

Of course they were done for the M100, but I tested on your images and the colors are a lot more similar to DPP. Unfortunately the Landscape icc doesn’t work so well. It could be several things: DPP makes a different mode for M100 (it’s a different sensor after all) or I did something wrong while doing this icc (which is also very likely).

Canon M100 Faithful icc:

Canon M100 Landscape icc: