Colour management (?) question

[CarrotMan]

(I have already sort of asked this question here, but not got a reply yet, so I’m revising it).

I inadvertently had ROMM RGB set instead of sRGB in AP colour setting preferences (sorry, haven’t got AP open at present, but I mean in the setting near the top of the menu). When opening a TIFF in AP, which had been converted from a Canon .Cr2 in Canon DPP, or from a Fuji .RAF in Silkypix  (these TIFFs being 8 bit sRGB), the colour looked fine. But if I opened a TIFF (again, 8 bit, sRGB) which I’d processed using DxO PhotoLab 2, the colour was awful and very over-saturated. But if I opened the same TIFF directly into AP by launching the “Export to application” function, the colour looked fine. I wonder why? It looks as though maybe opening the file from within AP makes the software use the ROMM profile, but launching AP from within PL2 somehow ignores it? (Everything is fine now I’ve changed the profile from ROMM to sRGB, I’m just curious about this issue).

 

[smadell]

It sounds like something has gone wrong when DxO exported your file. (Not sure why, since I’ve use DxOPhotoLab 1 in conjunction with Affinity Photo successfully for a long time!) However, if you’ve exported a file from DxO that is supposed to be an sRGB file but it is somehow opened in Affinity Photo with the assumption that it is a ROMM file, that would account for the wildly oversaturated color. (To demonstrate this, open an sRGB file and choose ASSIGN Profile (not Convert) and make AP think it’s a ROMM file. All of a sudden your sRGB values for red, green, and blue are describing bolder and more saturated colors.)

I’m not sure where this “lost in translation” step happened, but it’s pretty clear that your sRGB file is being displayed as if it’s a ROMM file.

[TomM1]

When I export an sRGB Tiff file from DXO, then open in Affinity, AP thinks it is a ProPhoto file and the colors are way off.

When opened, if I Assign sRGB it is corrected.

No issue when exporting Adobe1998 or ProPhoto.

 

[smadell]

I normally export from DxO as 16 bit TIFF files, using ProPhoto as the color space. I’m not sure if I ever exported using sRGB. If you examine the EXIF data of the exported TIFF file (not from within Affinity Photo, but the otherwise untouched file on your disk) does it have a Color Space of sRGB, or does it come out of DxO without an assigned color space?

If you’re on a Mac, you can open the TIFF into the Preview app and open the Inspector. That should let you know the color space inside of the file, if there is one.

I’ve never opened an sRGB file in AP and had it automatically assigned to the ProPhoto space. However, if the file doesn’t have an embedded color space, and if AP is set to do so (as the OP seems to indicate it initially was) the file might open as if it were a ProPhoto (ROMM) file.

[smadell]

I just this minute found a post on the DxO forum, basically titled “Critical Bug in PhotoLab 2 - sRGB profile missing on export.” I’ve included a link to the post below. However, this seems to be a very serious bug in version 2 of PhotoLab, and it explains the problems that you’re all having.

https://feedback.dxo.com/t/critical-bug-in-photolab-2-missing-srgb-icc-profile-during-export/8347

[TomM1]

I also do not regularly export sRGB.

Preview reports the test file as sRGB.

And there is no issue opening the same file in Photoshop.

[CarrotMan]

8 hours ago, smadell said:

I just this minute found a post on the DxO forum, basically titled “Critical Bug in PhotoLab 2 - sRGB profile missing on export.” I’ve included a link to the post below. However, this seems to be a very serious bug in version 2 of PhotoLab, and it explains the problems that you’re all having.

https://feedback.dxo.com/t/critical-bug-in-photolab-2-missing-srgb-icc-profile-during-export/8347

Thanks for this, it does look as though this is the source of the problem. I’ll get onto DxO again. It seems very odd that the sRGB profile is presumably attached to the TIFF which PL2 launches into Affinity, but somehow missing from the TIFF which PL2 exports to the Pictures folder. At least I know now that this is not an Affinity issue, and that AP is correctly  applying the set profile to a profile-less TIFF when opening the file from Pictures, but presumably finding a profile when the program is opened from inside PL2! Does this mean that PL2 creates two TIFFs, I wonder? 

I don’t tend to use PL2 and Affinity together much because of the known problems with Viveza, which means I tend to use PSE to apply Nik edits. I initially thought it was just another DxO - Affinity tiff (apologies for the awful pun!), so good to know that Affinity is “not guilty”.