Am 30.05.19 um 23:34 schrieb Benjamin Koppe:
Hello everyone,

I'm about creating a DIN Lang Folder brochure with ConTEXt. I got
everything set up the way I'd like it to. Now that I'm done with the
work, I've been told the output pdf should have a CMYK Color profile
embedded for the on demand printing service to be able to deal with the
file...

I am unsure what steps I have to take to make my output pdf compliant
with CMYK. I don't even know how I could verify it does indeed have
CMYK. Evince doesn't seem to show that info...

So if anybdy of you could give me some hints, that's be wonderful.

Cheers
De Benny

Hi Benny,

if you can read German you might find some hints in my articles about
creating din lang folders
https://www.hasecke.eu/post/werbemittel-mit-context-gestalten/

On colors read the second part:
https://www.hasecke.eu/post/wie-wir-bei-hostsharing-mit-context-arbeiten/

Search the mailing list for color profile questions because I had to ask
often to make my things work. ;-)

The wiki contains some hints, too.

What you can do is to create a mode like this:

\startmode[fogra39]

\doiffileelse{CoatedFOGRA39.icc}{}{\farbprofilnichtgefunden}
% This will be printed in log if context does not find the profile for
% some reason

\definecolor  [hs-logoblau]   [c=1.000, m=0.735, y=0.279, k=0.160]

\definecolor  [hs-dunkelblau] [c=0.844, m=0.544, y=0.070, k=0.000]

\definecolor  [hs-hellblau]   [c=0.468, m=0.220, y=0.086, k=0.002]

\definecolor  [hs-orange]     [c=0.127, m=0.832, y=1.000, k=0.042]

\setupcolors[cmyk=yes,rgb=no,]

\setupbackend[
   format=PDF/X-3:2003,
   intent={Coated FOGRA39 (ISO 12647-2:2004)},
   ]

\stopmode

If you call context with --mode=fogra39 you will get these color
definitions and the defined pdf format with the right profile (intent).

If you download additional icc profiles (eg. the fogra one is missing in
the context distribution) put them here:
context/tex/texmf-local/colors/icc

In this folder they won't be overwritten by an update.

There are some limitations in ConTeXt concerning colors as embedded
images are not converted, so RGB images are converted only by the print
shop during printing, which can lead to strange results. I think the
only way to control the output is to convert all images to CMYK by hand.
By doing this you can modify them to get the best results.

I hope that helps
juh
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://context.aanhet.net
archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net