These forums are now Read Only. If you have an Acrobat question, ask questions and get help from one of our experts.

How to keep total area coverage under 240%

Forum Index > Printing & Prepress > How to keep total area coverage under 240%
2009-04-10 15:12:28
pdf_novice
Registered: Feb 26 2009
Posts: 3

I have a pdf that is RGB. When I convert it to CMYK using
acrobat professional 8.0's "Convert Colors" option
(which is under advanced, print production)
I get a rich black that is
C 75%
M 68%
Y 67%
K 90%
with a total area coverage. My printer requires a total area coverage
of at most 240% (with rich black recommended as
C 60
M 40
Y 40
K 90)

I'd be most grateful if someone could tell me how to convert colors so that the
total area coverage is at most 240%, ideally with rich black coming in as above.

(I have not been able to find this topic in articles)

Thanks,
Roy

My Product Information:
Acrobat Pro 8.1.2, Windows
Top
2009-04-11 02:14:45
#1
UVSAR
Expert
Registered: Oct 29 2008
Posts: 1357
"By hand" color space conversion in Acrobat is not easy - the Acrobat color converter dialog is built around the concept you're using ICC color profiles to define how the printed document should behave, so tweaking a specific value is only possible by creating a custom ICC profile. [b]Ideally your printer should do that for you, as there's a lot more to an ICC profile than the TAC.[/b]

If they can send you one, then you can use it as the output intent in Acrobat's color converter panel, and it will automatically squish the CMYK values into the allowed range, ensuring the TAC is satisfied (but not guaranteeing it'll use that specific rich black combination). You can verify the final result using the Print Production..Output Preview menu item, which shows the TAC under the cursor.

There are commercial plugins for Acrobat which will create/edit profiles and even specify a particular RGB-CMYK relationship so you get a particular rich black (such as Prinect), but natively, inside Acrobat itself, building a new ICC profile isn't an option. We (i.e. the printer) can use Ink Manager to manually redefine colors, but that's designed for a different thing (plate mapping) and using it to crowbar the gamuts about without ruining the appearance of the document is a black art.

If you have Photoshop, you can build custom ICC profile files by starting a new image and crawling through the color manager (the profile defines everything you need; the color space - CMYK, etc - and sets things like the TAC), hoofing the newly-created profile into Acrobat to use when converting your PDFs. Google for it; there are many tutorials out there.

I would again stress: if your printer has a particular requirement they expect you to meet, they really should be giving you a profile file to install.
Top