CR3 and Color Management

Dear fellow FOSS and photography enthusiasts,

just like you, I want my pictures to be vibrant and rich. I recently bought a 90D, and was looking forward to play around with some RAW shots. Unfortunately, I quickly realized that my version of RawTherapee would not read the new .CR3 format. Weeks of attempting to install DPP4 with wine later, I ended up installing the latest version of RawTherapee, Another RawTherapee, and built Darktable - all of which should have CR3 support. The results have been less than satisfactory.

When opening my CR3s (shot in RAW + JPEG mode), I noticed that some images really did not look like the JPG equivalent. More on that later.

The no-headache solution was to simply use Adobe’s DNG converter to handle the .CR3 interpretation business, and produce a generally readable format, .dng. Great! I’m a pro at wine at this point, so this seems like a walk in the park. It turns out that the DNG files still look off in RAW editing. At this point I just need someone to explain this mess to me:
why can I not reproduce my camera’s JPEGs with the RAW files?

I’ll start showing what I’m used to, with the CR2 format. I’ll be using XnView, a color managed image previewer.

  1. Screenshot of the .CR2 with XnView.
  2. Output of RawTherapee of .CR2 with auto-matched camera profile.
  3. Output of RawTherapee of .dng with auto-matched camera profile.

This doesn’t look too bad, I recognize the same colors everywhere, although the purples seem to go a bit deeper with RAW. I’m not sure if this is a good or bad thing, but ok. I am convinced here that I have all the information I need when RAW editing. Moving on to CR3.

[I am only allowed to post 4 images, so keep reading in the comments]

Programs used:

RawTherapee 5.8 which should have CR3 support.

ART with even better CR3 support supposedly.

DarkTable following these instructions.

  1. Original JPEG produced by the camera.
  2. Screenshot of the .CR3 preview with XnView.
  3. Output of RawTherapee of .CR3 with camera standard profile.
  4. Output of RawTherapee of .dng with camera standard profile.
  5. Output of RawTherapee of .CR3 with camera standard profile, trying to match the saturation with the JPEG.
  6. Output of ART of .CR3 with camera standard profile.
  7. Output of DarkTable of .dng with some tweaking of saturation to bring out more colors.

(I couldn’t produce the darktable image for .CR3 because it wouldn’t read it, and the art image for .dng because it wouldn’t save it, go figure)
First of all, the XnView and original JPEG agree fairly well. I guess the .CR3 maybe has an embedded JPEG preview for the file which should be the same as the actual JPG. It quickly goes downhill with the RAW editing programs.

In RawTherapee, I’m left with what seems to be a faded image, and the same goes with ART and DarkTable. Even when I try to bring out the colors, you can clearly see that the reds are lacking compared to the JPEG. In addition to this, pushing the color to the extreme brings out noise in the image. Here again, the original and my best attempt in RawTherapee, side by side:

I’m left frustrated.

I want an assurance that I am truly playing with the full information of my images, and being able to perfectly reproduce the JPEGs would give some confidence that this is the case. I’m not able to do it. What gives?

Any help, explanation, or tips are welcome! Thank you!

Your first problem is you cannot reproduce your jpg…you need to understand the difference between the jpg and raw…raw is not a better jpg and you do not have the canon recipie at your disposal…this is the source of your frustration…there are a number of topic on this in the forum. I will try to dig up a reference…

You can try to use the jpg as a rough guide…but in truth when you want the jpg look use your jpg…If you want raw…then move on to raw editing…

First off, make sure you keep your .CR3 files: support for them seems to be in the pipeline, and when it arrives, you’ll be glad you still have them (it looks like .dng obtained from conversions are more throuble than they are worth if the corresponding raws can be handled).

The embedded jpeg in the raw files is indeed a small version of the in-camera jpeg, with all the processing the camera does, applied to it. Including any specific “scene” modes, styles and other personal settings.

That is also one of the reasons a file just opened in dt (or another raw editor) does not look like the camera jpeg. That does not mean you lose information. On the contrary, I noticed that my camera discarded up to 1 EV in the highlights, by applying an s-curve that’s too aggressive (but it does give a “nice” amount of contrast…).

Editing raw files is a learning process, you’ll get better at it in time, and then you’ll notice you can get more out of your images than the camera. I still go back to older images and re-edit them: my knowledge increases over time, and the programs evolve as well, and that’s after working with raw files for over 10 years.

For the image you posted, I think you are very close, and I actually prefer the more muted look in your edit, the original seems a bit over-saturated. And assuming the “white” top-left of the monogram is supposed to be white, the camera version is a bit too yellow

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If you have applied tone curves in RT you really need to try out the different variants…I think the default is film but there are about 5 or 6 and from this one selection you will start with very different versions of your image…


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Canon hasn’t shared the way Canon creates its JPEG files.

What I have seen is that Canon Digital Photo Professional 4 apply noise reduction even if I set NR to 0.

If you want a camera manufacturer’s look, check here Do you want a straight out of camera JPEG style in darktable? Here we help each other

I created some of the styles there thanks to darktable-chart

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the standard color matrix for the Canon 90D seems to be quite off – I don’t know why. You can try with the attached dcp profile (with RT or ART) and see if that helps. (55.0 KB)

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First off - if you like the JPG image, why are you interested in doing work processing the RAW image to match the JPG?

Surely the point of RAW is to make your own choices as to how the image should look - and that means mastering the tools that give you the choices . . .

That’s much better, thanks. Did you make this DCP yourself?

The reason why I want to reproduce the JPG image is to test whether the .CR3 support is working properly. I encountered some JPGs that were so different from what I could produce with RawTherapee, it made me wonder if the handling of the .CR3 was off. When using a different DCP (that agriggio provided) for the 90D, the colors already look much better.

First off, make sure you keep your .CR3 files: support for them seems to be in the pipeline, and when it arrives, you’ll be glad you still have them

This is also what I’m curious about: what is not currently taken into account with regards to .CR3 so far? I read something about the metadata… But yes; I archive all my raw files.

That does not mean you lose information. On the contrary, […]

Indeed, however with reverse-engineered format and self-made color profiles, I suppose there is room for error. Say the color profile is way off, and the reds are washed out in my RAWs. Surely pulling the reds back into place is due to cause some unnecessary noise?

If you have applied tone curves in RT you really need to try out the different variants…

Thanks! I haven’t played much with this, I’ll try it out.

@utext Others have said it before, but I’ll reiterate: never expect any software to produce a starting point close to your camera’s JPEG. The manufacturer has developed a raw->jpeg processing style that we as developers either cannot fully reproduce or do not even want to reproduce.
That being said, the default colorimetry should be correct. If the color matrix is off, your colors will be off. If Alberto’s DCP is much better, I’ll consider adopting it for RT as well. I’m curious to know how the DCP was made too.
I thought we had a pretty good profile in RT because of this and this?

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I had no idea RT has already a DCP profile for the 90d. I was talking about the Adobe colour matrix which seems off to me. Anyway, I’d bet the RT DCP is of better quality than what I generated (mine is based on dpreview’s test scenes btw)

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Wouldn’t it just be easier to take the one from Adobe?? It could also be tweaked in Adobe profile editor…I guess harder for Linux crew…

Point taken. I guess I was not expecting the JPG processing to go beyond balancing the exposure, and maybe adding a bit of contrast and saturation when needed.

Is there then a better way of verifying whether the colors are “off” or not?

I’ll keep playing around with my CR3s in RawTherapee and see if I’m able to get the results that I want. Thanks for everyone who participated in the thread!

Well if you have everything calibrated …ie your monitor and your camera then you could use the picker and see what color you get for the patches wrt the published values as an estimate. I suspect also there are either online tools or other ways to evaluate the profile in terms of delta E values to show how accurate it is (I think Argyll will do it)…but if you have neither calibrated and are going by sight its not of much values esp as what you see is then likely to be quite different to what others will see on their hardware…