CMY100K converts TEXT to RGB color space when exporting to PDF

[girodimo]

Using the object inspector in Adobe Acrobat shows that the TEXT color space is converted to DeviceRGB. If I change the black amount to anything other than 100%black, CMYK values are preserved. For example, 99%black keeps the color space CMYK and CMY99%K. I tested this with vector images and had no problems. 100%black images stay in the CMYK color space and preserve the CMYK values. 

Is there some text setting like I'm missing to avoid this RGB mess?  Thanks.

 

[Ldina]

@girodimo There are a lot of "unknowns" in your request. I suggest you upload a sample Affinity file causing the problem, along with a screenshot of all your PDF export settings, including the checkboxes in the PDF export dialog window. A number of things can cause colors to be recalculated. I assume you defined your original colors using the CMYK Sliders and locked them (the little padlock to the left of the "CMYK" dropdown box). 

[werfox]

Hi @girodimo,

could you provide some informations:

1. Is the document’s colour setting set correctly to CMYK/8?
2. If 1. is set correctly: which PDF setting did you use to export?
   As @Ldina already mentioned, screenshots of the complete export settings box would be helpful.
3. Could you upload the document and the exported pdf here?
   If it is not possible, maybe someone of the Serif staff would provide a private Dropbox upload link.

[girodimo]

Thanks for the responses.

1. I’m using the 2.5.7 version of Affinity Publisher.
2. The color profile is set to CMYK/8, Japan Color 2001 Coated
3. I  tried PDF/X-1a, PDF X/-3, PDF X/-4, Press Ready -all with the same result.
4. I used the CMYK sliders to select the color and locked the color space.

The screenshots from Adobe show the values when the texts are selected.

untitled.pdf

[girodimo]

I was curious to see if I could get as close to 100% black with 8bit sliders. I set the black slider to 254. To my surprise, it "rounds up" to 100%black and stays in the CYMK color space. This is good enough for me for the time being. I want to get a file to the printer.

That being said, I feel extremely aggravated at the moment and I know I'm beating a dead horse here. For me, there is a lot of unexpected/odd behavior with Affinity. Sorting through the forums, trying to find out if it's actually expected behavior, a feature or a new bug is trying. OK, I'm done, breathing deeply now. 

Thanks for anyone working on this.  

[Ldina]

@girodimo I looked at your uploaded PDF in Acrobat 10 Pro. It Preflights as fully compliant with PDF/X-1a (PDF v1.4), Japan Color 2001 Coated, and your blacks measure exactly as defined in Publisher (0/0/0/100, and 0/0/0/99 CMYK), based on your screenshots. So, based on what you've provided, it looks correct to me. You didn't upload your Publisher file or ALL the settings in your PDF export, as requested, so I can't really offer much more.

If you were using the CMYK sliders, you can only enter 0 to 100 for C,M,Y, K, each in 1% increments, so you can't enter 254 in CMYK (which is an RGB unit of measurement). 

So, I'm not sure what the problem is. Publisher can be very particular when it comes to PDF exports, preserving 100K blacks, color conversion and vectors. So the files have to be constructed properly, and you need to select the right PDF export settings to make sure you get what you need. 

[girodimo]

Thanks for looking at the file @Ldina. 

1 hour ago, Ldina said:

If you were using the CMYK sliders, you can only enter 0 to 100 for C,M,Y, K, each in 1% increments, so you can't enter 254 in CMYK (which is an RGB unit of measurement). 

It seems Affinity Publisher disagrees.

  

You can enter up to 255 with 8bit option selected.

1 hour ago, Ldina said:

It Preflights as fully compliant with PDF/X-1a (PDF v1.4), Japan Color 2001 Coated, and your blacks measure exactly as defined in Publisher (0/0/0/100, and 0/0/0/99 CMYK), based on your screenshots

You pre-flighted with with Acrobat Pro 10 and everything was as expected. It got me thinking that maybe it was an Acrobat setting issue. It turns out, it was. The screenshot below shows my Acrobat Pro 9 Preferences window. Unchecking the [Replace Document Colors] box does the trick. I don't why this was checked, but unfortunately, it was. Ahhh!

 

Hopefully, this helps others.  Good Day!

 

[Ldina]

Ha...thanks, I've always worked in percentages with CMYK (in Adobe and Affinity) and didn't even know the 8-bit option was there! Affinity is probably rounding the 0-255 values to 0-100% in one percent increments. 

Glad you got it sorted and all is well. 

 

[Ldina]

@girodimo This discussion piqued my curiosity and I wanted to see how using 8-bit CMYK values would be seen in Acrobat 10 Pro. You probably know already, having played around with it.

I created text and rectangles with 100K, 99K, 255K, 254K, 253K, 252K and 251K, (CMY=0), then exported to PDF/X-1a (default settings, using US Web Coated SWOP v2). In Acrobat Pro's Output Preview, hovering over the various shades of black displays the values rounded to integers as Percentage K values. That's what Affinity Publisher is also doing if the CMYK color panel is set to 'Percentage', which is the default. If you switch back to 8-bit in Publisher, the 0-255 K values are retained as entered originally.

If you switch to the Object Inspector in Acrobat, all those K values (whether created using percentage or 8-bit) are displayed in 0-1 floating point. So, 100K shows as 1.0. The good news is that all the 8-bit values defined in Publisher are retained, providing the user with finer control over tones (i.e., 256 possible shades instead of 100). That could be particularly useful, especially at the light end of the tonal scale. 

Also worth noting is that in Publisher, 100K (or 255K) defaults to "overprint". For any shade less that 100K, the default behavior is "overprint=false". 

K Test 8bit vs Pct.afpub K Test 8bit vs Pct.pdf