EPS Files Display Incorrectly in macOS Affinity Apps when using Device CMYK Colour Palettes

[Hangman]

Hi @Dan C,

I was unsure whether to raise this as a new thread or continue an older, potentially related thread, but decided to start a new thread because I now have, what appears to be a repeatable formula to reproduce the issue and so have linked the other two, possibly related, threads at the end of this post should they all need to be merged.

The CSV Pantone libraries used by the Affinity apps are defined using either sRGB only or sRGB and CMYK colour values, i.e., these palettes combine sRGB and CMYK colour references in the same palette...

• PANTONE Color Bridge Coated V5.csv
• PANTONE Color Bridge Uncoated V5.csv
• PANTONE GoeBridge Coated.csv
• PANTONE Plus CMYK Coated.csv
• PANTONE Plus CMYK Uncoated.csv

The remaining palettes use sRGB colour references only...

There is a bug in the macOS version of the Affinity apps (appearing in a couple of different posts), logged as AFD-6216, where EPS files created in third-party apps, in certain circumstances, display CMYK values of 50% and above as exactly 50% when opened in Affinity apps. A few instances of this issue have involved EPS files created in Illustrator, though I've now created files in VectorStyler demonstrating the same exact issue.

Note 1: I don't believe the issue itself is either an Illustrator or Vectorstyler problem and it is likely possible to create using any third-party vector software following the same process.

Note 2: The EPS files open correctly in V1 of the Affinity Apps but incorrectly in V2.

Note 3: EPS files created directly in Affinity Apps, using the same colour palettes do not demonstrate the issue when the exported EPS file is opened in either Affinity or third-party apps.

As far as I'm aware the issue is Mac-specific and to date, I don't think there's been a specific formula to recreate the problem but some additional testing seems to suggest the following...

Third-party apps generating CMYK EPS files using colour palettes defined using combined sRGB and CMYK colour values, result in DeviceCMYK colour definitions while those using sRGB only colour values in the colour palette result in DeviceRGB colour definitions in the exported EPS file, while in both cases, the colour is defined using CMYK values in Affinity apps.

It appears that in V2 of the Affinity apps, any EPS file that uses DeviceCMYK as its colour definition incorrectly interprets CMYK values above 50%, regardless of the value between 50% and 100% and subsequently displays those values at exactly 50%. In the V1 Affinity apps, the same file is correctly interpreted.

Testing this with any palette that combines sRGB and CMYK values in the same colour palette (whether an ASE, CSV, XML or JSON third-party palette), produces the same incorrect CMYK values in Affinity 2 apps.

When looking at both the DeviceRGB and DeviceCMYK colour values in the EPS files themselves, they are shown correctly and perfectly match the values shown in the respective palettes.

Affinity Designer v1 - sRGB only Defined Colour Palette - DeviceRGB Colours Correctly Displayed

 

Affinity Designer v2 - sRGB only Defined Colour Palette - DeviceRGB Colours Correctly Displayed

 

Affinity Designer v1 - sRGB and CMYK Defined Colour Palette - DeviceCMYK Colours Correctly Displayed

 

Affinity Designer v2 - sRGB and CMYK Defined Colour Palette - DeviceCMYK Colours Incorrectly Displayed

 

Affinity Designer v1 - sRGB and CMYK Defined Colour Palette - DeviceCMYK Colours Correctly Displayed

 

Affinity Designer v2 - sRGB and CMYK Defined Colour Palette - DeviceCMYK Colours Incorrectly Displayed

 

Links to Two Other Posts Demonstrating Similar Issues

Interestingly, the Illustrator files uploaded in both posts are missing their EPS Hex Signature but reinstating the correct signature makes no difference to how the same files appear when opened in V1 vs V2.

 

Logo Italian Embassy

 

CD Artwork

 

Sample EPS Files

CB Coated LAB Swatches.eps

CB Coated RGB and CMYK Swatches.eps

RAL RGB Only Swatches.eps

RAL RGB and CMYK Swatches.eps

 

[NathanC]

Hi @Hangman,

As you've pointed out there is an issue logged under AFD-6216 which details the same issue as what you've shown with CMYK values >50% being imported incorrectly at 50%, the issue missing some specifics which you've outlined here, such as the palette needing both a CMYK and RGB colour definition for the bug to trigger and the 3rd party app requirement.

To avoid any confusion by logging the same issue twice i've now updated the existing issue with the details of your report along with your sample files which better demonstrate the issue. 

I've also since found that this is a regression between 1.10.5 and 1.10.6, if you open any of your .EPS files in 1.10.6 you should encounter the same issue with the .EPS CMYK values being capped at 50%, I'm guessing you're still running 1.10.5 if this is still working for you?

Thanks again for the level of detail and sample files. 🙂

[Hangman]

Hi @NathanC,

Thanks for the update and for adding these details to the existing bug report.

Yes, this is indeed a regression between 1.10.5 and 1.10.6 carried over into 2.X, I've been testing in both 1.10.5 and 1.10.6.

One additional point to add, which may or may not be related to this bug and which I've previously raised with @Dan C is that while LAB values are supported in the Adobe Swatch Exchange (ASE) format, when importing ASE files into Affinity Apps that use LAB colour definitions the palette imports minus any LAB defined swatches e.g.,

PANTONE+ Solid Coated-V3.ase

This is an XML version of the same palette for legibility...

PANTONE+ Solid Coated-V3.xml

If you open the ASE version in Affinity you will see the palette name but no swatches, open the same palette in other vector-based apps and the all works correctly.

The reason for mentioning it is that in the first linked post, Logo Italian Embassy, the last screengrab of the first post in that thread shows the original file as created in Illustrator. If you take a look at the Illustrator swatches palette in that screengrab you'll see that the colours are defined using LAB values, defined by the colour icon to the right of the three Pantone colours used in the artwork. These are interpreted as CMYK Custom Colours in the eps file rather than as RGB and equally demonstrate the same bug when the eps file is opened in Affinity apps 1.10.6 and above.

Maybe totally unrelated but I thought it worth adding to the mix just in case it plays a part in the equation.

[SamMN]

I realise this post is from a while ago so would've thought this had been patched by now, but I think something like this is still occurring.
My colleague and I are both running the latest version of Affinity Publisher 2 (2.4.0), both on Mac OS Sonoma, but we get consistently different results when opening the same EPS file (attached).

With both our colour profiles set to FOGRA39 for CMYK, and sRGB for RGB, when I open the attached file I get a pure black logo (CMYK8, all values 0 apart from K which is 100). Colleague gets all values 0 apart from K which is 50.

Though I'm not sure why we're getting different results when we're running the same version of Publisher on the same settings (etc)?

Degruyter logo.eps

[Hangman]

19 minutes ago, SamMN said:

With both our colour profiles set to FOGRA39 for CMYK, and sRGB for RGB, when I open the attached file I get a pure black logo (CMYK8, all values 0 apart from K which is 100). Colleague gets all values 0 apart from K which is 50.

Though I'm not sure why we're getting different results when we're running the same version of Publisher on the same settings (etc)?

I see the same as your colleague, i.e., K50...

I'm equally baffled as to how or why you see K100, despite K100 being the correct value... This postscript interpretation bug has existed for a long time unfortunately and I don't know whether we will ever see a fix as I think it's a limited use case but it would be good if this can be at least bumped...