Problem loading files with no embedded profile

[Samoreen]

Hi,

Assuming I'm trying to load in AP TIFF files that are tagged as sRGB but with no embedded profile. My AP working color space is ROMM RGB (Prophoto). In that case, the sRGB profile should be assumed (W3C/ICC). But AP is obviously displaying the wrong oversaturated colors. If I change the working color space to sRGB, there's no problem.

I'm not aware of any other application having this problem. All the image handling applications/viewers/browsers I'm using are displaying these files with the correct colors. Attached are the AP version and the PS version (same file, correct colors). I get the same result with all other applications/viewers/browsers as in PS. Same result if I disable the “Convert opened files to working space” option.

[stokerg]

Hi @Samoreen,

Could you attach the TIFF file you are using?

Also what's your working colour space in PS?

[Samoreen]

35 minutes ago, stokerg said:

Could you attach the TIFF file you are using?

Hi,

The file is available here : https://www.dropbox.com/s/vim1efzta4uhxm6/Color_issue.tif?dl=0

It's just an example.

35 minutes ago, stokerg said:

Also what's your working colour space in PS?

Prophoto. The file was not created in PS, though. However, I made another test. I opened the original RAW file in PS and exported it as sRGB/TIFF (the sRGB profile was embedded). There was no color shift when opening it in AP. Then, I stripped the profile out (the sRGB tag still being there) and re-opened the file in AP. The color problem was back.

But PS is also just an example. Whatever the application into which I load this file, there's no color problem. I can open it in Paint, Paint.net, Silkypix Developer Studio, Lightroom, FastStone Image Viewer, Windows Image Viewer or any other image handling application or color managed browser, the colors are correctly displayed. Only AP appears to be disturbed by the lack of an embedded profile. Normally, when no profile is embedded, sRGB should be assumed (especially when the file is tagged as sRGB).

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[Samoreen]

23 minutes ago, Lagarto said:

I can reproduce this on Windows version of Photo, both release version and latest beta.

Hi,

Using my file or one of your own ?

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[Samoreen]

38 minutes ago, Lagarto said:

Which app was used to save this TIFF file?

DxO Photolab 4. DPL 4 (and previous versions) doesn't embed the ICC profile when exporting as sRGB. Which is legitimate, according to the W3C/ICC recommendations. Most applications behaves correctly in this case, AP obviously has a problem.

 

38 minutes ago, Lagarto said:

Based on filesize it does not appear as if PS actually embeds the profile or just tags it, but I cannot be say for sure

You can check whether an ICC profile is embedded with this Exiftool command :

exiftool -icc_profile:* filename

[Samoreen]

37 minutes ago, Lagarto said:

When "Saved as" as TiFF from PS (2021) or Photo, with sRGB profile checked, there is no error.

Yes, in this case, PS embeds the profile. But if you strip the profile out, AP will display wrong colors, even if the sRGB tag is still there.

In order to strip the profile out, you can use Image Magick on the command line :

magick <original_filename> -strip <stripped_file_name>

 

[Samoreen]

35 minutes ago, Lagarto said:

...so PhotoLab  appears to tag the color profile in TIFF files in a way not supported by Affinity Photo.

If I remember well, in earlier versions, AP was using Exiftool to read Exif info from the loaded file but it seems that they are now using their own code.

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