Color Profiles and Soft Proofing

[Freixas]

My work flow is this: RAW image -> DxO PhotoLab 7 with ProPhoto color profile -> export to TIFF with ProPhoto color profile -> import to Affinity Photo with ProPhoto color profile -> export to JPG with sRGB IEC61966-2.1 profile -> view with IrfanView or MS Photo.

There is a small but noticeable color shift when I compare the image in Affinity with the image in IrfanView. If I save the JPG using the ProPhoto color profile and then view with IrfanView, the images look identical.

My assumption is that the sRGB color space cannot display all the colors in the ProPhoto color space. Fine. But let's keep in mind that neither can my monitor. I would think that a color in the ProPhoto color space outside of my monitor's color space would be converted to my monitor's color space, which shouldn't be much different than the result of converting it to sRGB. I wouldn't think the image colors would appear different.

Of course, there is intent. My working color space is RGB/16, ProPhoto Perceptual with no Black Point compensation. When I export to a JPG with an embedded sRGB IEC61966-2.1 profile, I'm not seeing any place to declare the intent.

In any case, I thought I would enable soft proofing using the sRGB IEC61966-2.1 profile—then I could at least preview what would happen. I added a Soft Proof adjustment with the sRGB IEC61966-2.1 profile and Perceptual intent. The image didn't change. If I enable the Gamut Check, it shows that there are gamut problems, but that's about all it does. I tried various other intents as well—the image remains unchanged.

To preview the color shift from ProPhoto to sRGB, I seem to have to convert the document's color profile. Do I misunderstand the Soft Proof adjustment?

[thomaso]

10 hours ago, Freixas said:

I thought I would enable soft proofing using the sRGB IEC61966-2.1 profile—then I could at least preview what would happen. I added a Soft Proof adjustment with the sRGB IEC61966-2.1 profile

There are known issues with Soft Proof in Affinity (e.g. https://forum.affinity.serif.com/index.php?/search/&tags=AFP-5179'*).
*EDIT: with Stokerg's response below it seems the tag 'AFP-5179' has turned to 'AF-820'. https://forum.affinity.serif.com/index.php?/search/&tags=AF-820

For the issue with sRGB @lacerto posted a workaround that uses an updated sRGB profile:

Edited October 20, 2023 by thomaso

[Freixas]

3 hours ago, thomaso said:

There are known issues with Soft Proof in Affinity (e.g. https://forum.affinity.serif.com/index.php?/search/&tags=AFP-5179').

For the issue with sRGB @lacerto posted a workaround that uses an updated sRGB profile:

Thanks. Using the sRGB2014.icc profile for soft proofing shows the same result as saving with the sRGB IEC61966-2.1 and thus makes soft proofing possible.

The process is not ideal although this gives me a fighting chance. The sRGB space is perfectly capable of representing the colors I want. This is easy to see by converting the image to sRGB and then increasing the saturation a bit. Affinity is already mapping the ProPhoto space down to the monitor's color space. It still seems as though converting to sRGB shouldn't change what I see on the screen.

Since sRGB has been the default for images without profiles and for programs that don't pay attention to color profiles, I use sRGB for JPGs intended to be shared with others. My workflow seems more complicated than it should be: get the image looking the way I want, the soft proof it in sRGB and correct any color shifts. And the corrections have to be guesses—once I change the soft proof,  the original image will now be incorrect. This just doesn't seem right.

[lacerto]

 

3 hours ago, Freixas said:

My workflow seems more complicated than it should be: get the image looking the way I want, the soft proof it in sRGB and correct any color shifts. And the corrections have to be guesses—once I change the soft proof,  the original image will now be incorrect. This just doesn't seem right.

It does seem more complicated than it should: why not just convert any wide-gamut (> any larger color gamut than sRGB) image to sRGB so that you work with final color values and directly see what you get (when exporting)? If you do need to retain the wider color space and the original image, it is easier to make a copy of the original and work with a copy than making changes to the original using a soft proof, then turning off soft proof, exporting image (without embedding the profile), and finally closing the image without saving it.

Direct color profile based conversion (also when using Affinity apps) generally also does a much better job (and allows using diverse options and conversion intents) than manual adjustments (e.g. using HSL etc. controls), especially within Affinity apps where these options do not seem to have any effect in context of Soft Proof adjustment (but do work in context of conversion). 

More generally: even when working within a limited display gamut, converting between different color profiles and bit depths -- and color intents, black compensation and dithering -- can have significant effects on visual appearance within sRGB (or below) color space. The clip below demonstrates, within a bit convoluted environment, doing a profile conversion on a natively wide-gamut display on a Windows computer, but viewed through sRGB-limited MacBook Air via Remote Desktop, to avoid color compression that would happen if trying to record the video directly on a mac (so that actual change of visual appearance shown on macOS Photoshop doing the same conversion on an sRGB limited MacBook Air would be lost in recording).

 

[stokerg]

HI @Freixas,

I've updated the bug report for the Soft-proofing bug with a link back to this thread, so we can update you when thats been resolved.

 

[Freixas]

7 hours ago, lacerto said:

It does seem more complicated than it should: why not just convert any wide-gamut (> any larger color gamut than sRGB) image to sRGB so that you work with final color values and directly see what you get (when exporting)?

Yes, I am re-thinking my workflow. The original images stay in ProPhoto, but when an image is intended for Facebook (which seems to always convert images to sRGB), I might as well start with sRGB.

I also think I might be wrong in saying my monitor's color space is smaller than sRGB. It's rated for 100% of the sRGB color space. Someone claimed that it covers 90.7% of the Adobe RGB color space. It's possible the colors I can see on the monitor cannot be reproduced in sRGB.

I ran through a series of photos. Most images survived the conversion to sRGB reasonably well. One deeply red image was pretty far off.

The Soft Proofing adjustment is buggy. The gamut warning fails to update as I make changes to the image. And the conversion to sRGB, even when it seems to work initially when using the sRGB2014.icc profile, gets off track as I make adjustments. The adjusted image, with Soft Proofing on doesn't look like the converted exported image.

Switching to the sRGB color space might be the best approach.

[stuck]

16 hours ago, Freixas said:

DxO PhotoLab 7 with ProPhoto color profile

I'm not sure what you mean by this because DxO PhotoLab does not use ProPhoto as it's working colour space.  It only offers the choice of either:

'legacy', which means Adobe RGB

or:

'DxO Wide Gamut', which is a propriety colour space invented by DxO and which is close to, but not identical to, Rec. 2020 (see the last paragraph on the third link below)

Once you have finalised your edits and are ready to export your file then PL does offer a variety of profiles, including ProPhoto thus I do understand your next step:

16 hours ago, Freixas said:

export to TIFF with ProPhoto color profile

There is more on DxO's Wide Gamut colour space here:

https://support.dxo.com/hc/en-us/articles/6754299074077-What-color-space-does-DxO-PhotoLab-use-

https://www.dxo.com/technology/wide-gamut/

https://www.dxo.com/news/white-paper-wide-gamut/

[Freixas]

17 minutes ago, stuck said:

I'm not sure what you mean by this because DxO PhotoLab does not use ProPhoto as it's working colour space.  It only offers the choice of either:

Thanks for the correction. Yes, I'm using Wide Gamut. Yes, I'm exporting as ProPhoto. PhotoLab 7 just added a soft-proofing feature. I haven't done much with it. My quick tests seem to say that it works.

But my question was about optimal workflow. My original image is RAW, which has no color space (or maybe it has an intrinsic color space defined by the hardware). As I work with the image, I'd like to have the widest range of color possible, which I believe is effectively limited to what my monitor can display. Once I have my "ideal" reference image, then I can worry about how to adapt it to sRGB or to a print profile.

So the revised workflow I am considering is: RAW image -> DxO PhotoLab 7 with Wide Gamut color space -> export to TIFF with ProPhoto color profile -> import to Affinity Photo with ProPhoto color profile -> convert to target profile -> do the best I can to match the reference TIFF image -> export or print with target profile

[stuck]

My workflow is similar to yours except I'm still on DxO PL5 (still thinking about upgrading to PL7).  Thus my RAW files are converted in PL5 / Adobe RGB and exported to TIFF with Adobe RGB and opened in Affinity Photo 2 working in Adobe RGB.  Meanwhile my Dell monitor is hardware calibrate to its 'native' gamut, which if the X-Rite software is to be believed is a little bigger than Adobe RGB thus (I think) I can see all the colours that I've got in my TIFF.

Once I've finalised an image I'll save it as a .afphoto file.  If I'm going to print I'll usually do that direct from Photo 2 and what I get out of the printer is a good (enough for me) match to what I see on screen.  Sometimes though I want greater control over the placing of an image on the paper so I export another TIFF with Adobe RGB and then open that new TIFF in an ancient version of PhotoShop with Adobe RGB as its working space and print from there.  Again, what comes out the printer is acceptable.

If I want to share an image then, starting from the finalised .afphoto file in Photo 2, I convert it to sRGB using Relative Colourimetric intent with black point compression.  I rarely see any colour shifts as a result of that conversion.  After the conversion, I'll export a JPEG with an embedded sRGB profile.

[stuck]

Forgot to add...

If I have converted my .afphoto file to sRGB and then exported a sRGB JPEG, I don't resave the .afphoto file, because the .afphoto file is the master version of the finalised image.

[Freixas]

12 minutes ago, stuck said:

If I have converted my .afphoto file to sRGB and then exported a sRGB JPEG, I don't resave the .afphoto file, because the .afphoto file is the master version of the finalised image.

Understood. After dealing with a lot more images using my new flow, I think your luck with lack of color shifts depends a lot on the image you start with. Most of the images I've tried have few problems. Sometimes there are tiny color shifts in a few areas. I took a photo of a very red fall leaf, though, and it was tough to get anything close to the master image. I also had some very green leaves that became slightly but noticeably less saturated—that was the image that started my post.

The color space for most papers is even more limited than sRGB (I think), so it's great if you're having so few problems. Some images drive me to tears. One can calibrate a printer all day, but in the end, if you put it in a room with variable lighting, the image can go from bright to muddy over the course of a day. But that's the way it is with prints...

[stuck]

14 hours ago, Freixas said:

lack of color shifts depends a lot on the image you start with

Yes!

14 hours ago, Freixas said:

a very red fall leaf... ...very green leaves

Indeed, deep saturated colours are tricky.

 

14 hours ago, Freixas said:

it's great if you're having so few problems

But I'm only a casual amateur, printing for my own pleasure.  I don't claim that my prints are 'gallery ready'.

14 hours ago, Freixas said:

in the end, if you put it in a room with variable lighting, the image can go from bright to muddy over the course of a day. But that's the way it is with prints...

Yup, been there, done that, got the t-shirt 😁  Only yesterday I printed a shot of some golden autumn leaves that does just that.