Why is my black text separating in ID CS?

[Lou_Dina@adobeforums.com]

I'm using ID CS on a Windows XP platform. I recently designed a 4/C flyer using US Sheetfed Coated as my color space, since I wasn't sure who I was sending the job to for final offset printing.

The prepress people said when they converted from US Sheetfed Coated to their color space, the text separated into CMYK components and ended up on all their plates. Not Good!

I want black type to show up only on the black plate. Perhaps I missed something in my setup. I used the standard black swatch when I designed the piece.

Why does this happen and is there anything I can do to keep it from happening within ID CS?

Thanks,

Lou Dina

[Robert_Levine@adobeforums.com]

Did you send a PDF or the native files? If the native files, then the
problem is on the printers end if you indeed used 100% black.

Bob

[Ken_Grace@adobeforums.com]

I vaguely recall using US Sheetfed Coated as a profile and the same thing
happening. Try a different profile or none at all. I guess this profile
makes a rich black, which is why your text is on all plates.

k

[Lou_Dina@adobeforums.com]

Thanks, guys.

Bob...I sent the native ID CS file. I rechecked and I used the predefined 100K swatch for all text.

Ken, US Sheetfed creates rich black from the 100K swatch? That's odd. I'll have to look into that.

If you have any more insights, let me know. I'm wondering if it might have anything to do with the RIP they are using???

Thanks, Lou

[Gernot_Hoffmann@adobeforums.com]

Lou,

tell them they should use no input profile. In other words:
no CMYK conversion. The numbers as they are.

Going through TWO profiles cannot retain K-only, with one
exception: a switch like "use K-only if black less 1%"
(as in the Best Colorproof proof printing system).
The formulation "less 1%" is not really understandable but
it works.

Best regards --Gernot Hoffmann

[Lou_Dina@adobeforums.com]

Thanks, Gernot. I will pass this along to my commercial printer.

Regards, Lou

[Gernot_Hoffmann@adobeforums.com]

Lou,

you are welcome. Here is the missing explanation:
The profile connection space between two CMYK profiles
is Lab which has only three channels.
Lab cannot distinguish "K-only" and "Rich black".

Best regards --Gernot Hoffmann

[Lou_Dina@adobeforums.com]

Gernot,

Thanks again. That makes perfect sense.

So, if I design a document in ID in US Sheetfed Coated, how would I get it into the profile of the press and still retain solid black text on just the K plate?

And what happens when I take an ID document and create a PDF/X1a document, converting to the final press space? Will I get black text on 4 plates here too?

Thanks,

Lou

[Gernot_Hoffmann@adobeforums.com]

Lou,

The best choice: convert your images from RGB to the
appropriate FINAL CMYK space. Define your text by K-only.
Don´t allow a further CMYK conversion.

If a CMYK--CMYK conversion should be necessary,then it
depends IMO on the options of the RIP for the imagesetter.
If there is no switch "retain K-only for black text" then
one should have this alternative:
Convert only raster images. Don´t convert text and vector
graphics.

I did read the PDF/X1a. But I don´t know whether an AUTOMATIC
conversion would really work correctly.
Therefore the suggestion: Check in Distiller Color Settings
Input File None
Leave Color Unchanged
Rendering Intent Default

My experience is restricted to proof printing. Here is every-
thing under my control.
In your case the service provider should know how to handle
the separation correctly.

Maybe these input are helpful for a clarification.

Best regards --Gernot Hoffmann

[Lou_Dina@adobeforums.com]

Gernot,

Great answers. Thanks.....You're the man!

Lou

[Lou_Dina@adobeforums.com]

Some Answers....

Thanks to all for your input. It was pretty much right on. I found the following after much searching in Real World Color Management, and I thought I would share it in case anyone else is pulling their hair out due to their black text separating into a rich black process builds during conversion.

Black Preservation and Device-Dependent Data

"One of our biggest reasons for avoiding CMYK to CMYK conversions is that K-only elements such as black text or black-only drop shadows almost always wind up being converted to a rich black that contains other inks besides black. This is almost never a desirable outcome since it introduces all kinds of registration problems on press.

The simplest solution for page-layout applications is to define all native elements in RGB so they can be repurposed, and to define black-only text and anything else for which you want specific CMYK values preserved in CMYK. Then ensure that their CMYK source profile is the same as the destination profile to prevent conversion."

That last line is the key. If I do a CMYK to CMYK conversion, I now know (as Gernot correctly pointed out), that the LAB profile connection space will not know what to do with K only and will create its own rich black build in the destination profile. That will force me to reselect these K-only elements after conversion and redefine them as K-only. Or, better yet, define them in the final space up front to prevent any conversion.

Preserving K-only elements during conversion seems such an obvious needed addition to InDesign. A checkbox offering the choice to convert or not convert seems like it should be added.

Regards,

Lou

[Gernot_Hoffmann@adobeforums.com]

Lou,

I´m glad that I could add some useful information.
Now, here is my workflow:

1. Leave images as RGB.
2. Edit text and vector graphics as CMYK
using an appropriate swatch book.
3. Make PDF with compression and downsampling
for inspection via Web. Leave Color Unchanged.
4. Make PDF without compression with downsampling
if above 288 (I´m using always multiples of 72).
Leave Color Unchanged.
This is the final PARENT file. Can be called
RGB-PDF (though it contains already CMYK objects).
5. Make CHILD files in CMYK by Quite a Box of Tricks
using a specific CMYK profile. E.g.
CMYK-Euroscale-PDF with Euroscale Coated
CMYK-ISOCoated-PDF with ISOCoated
6. The CMYK-PDFs are at least partly proof printed.
7. The Printer (Service Provider) can use either CMYK-
PDF or he can convert the RGB-PDF using his preferred
profile.
Maybe he has to do this in order to add trapping and
overprinting.
Or is this possible directly for the CMYK-PDF ?

Best regards --Gernot Hoffmann

[Lou_Dina@adobeforums.com]

Hi Gernot,

"The Printer (Service Provider) can use either CMYK-PDF or he can convert the RGB-PDF using his preferred profile. Maybe he has to do this in order to add trapping and overprinting. Or is this possible directly for the CMYK-PDF ?"

I have sent PDF files to printers converted to their final CMYK space (using their supplied profile) and they can trap the PDF. The printers I have dealt with usually use separate trapping software. I prefer to let them do all imposition and trapping, since it is beyond me and I don't want the responsibility of screwing it up!

Thanks for sharing your workflow. I love the Adobe CS products, but will be glad to see them further integrate their products. I'd say Creative Suite is a "semi-suite" at this point, especially when it comes to managing color. It's slow, but they are getting there.

I wish they would get InDesign, Illustrator, Photoshop and Acrobat to seamlessly manage color, then come out with a RIP that works 100% with their products. They could offer the entire package to printers, pre-press houses, and designers. What a concept! That would kill Quark for good if they could make it less cumbersome and more reliable.

Lou

[rich_kidd@adobeforums.com]

Following up here, we've just had the same problems. We used to directly export to PDF with no problems, then were advised to move to Postscript->Distiller to be more reliable. At the same time we introduced some colour management using the Euroscale Uncoated setting.

The first job we output got spat back with CMYK text, and trying to avoid this seems to be really unpredictable - so far in my tests Printing to Postscript/Distiller PPD with InRIP Separations gives black text all the time, Printing with Composite CMYK or Composite Leave Unchanged gives us CMYK, and Exporting to PDF with Colour: Leave Unchanged or CMYK gives black text sometimes but not others.

Can anyone recommend the closest thing to safe settings?

Thanks

Rich

[Gernot_Hoffmann@adobeforums.com]

Rich,

IMO the best method is Export to PDF or Print as PS to File
and Then Distill with Leave Color Unchanged (the result is
the same).
No color management. CMYK values should be end products.

Best ColorProof has an option like "Print by K-only if black
....followed by a threshold". The correct setting of this
threshold (it´s 1%, which can hardly be explained) guarantees
that different percentages of K-only black are printed by K-only.

PosterShop Pro doesn´t need such a special setting. 50% K text
is printed as expected by rastered K-only.

We can see that the handling of "Gray" is neither standardized
nor reliable.

At least one can test how all the different grays are handled
by the RIP (doc about 170Kbytes):
<http://www.fho-emden.de/~hoffmann/a3gencolortest.pdf>

Resumed:
The print results for all kind of grays by different desktop
printers and different RIPs are not predictable.

My tests are valid for printers. No experience with image-
setters (besides "printing" clean programmed PostScript docs).

Best regards --Gernot Hoffmann

[rich_kidd@adobeforums.com]

Gernot

Thanks very much for the advice. Just to summarise my results if it helps anyone else in future:
1. Postscript, PPD=Acrobat Distiller, Output|Colour=Composite CMYK, Distiller settings leave colour unchanged - get CMYK text
2. Postscript, PPD=Acrobat Distiller, Output|Colour=Composite Leave Unchanged, Distiller settings leave colour unchanged - get CMYK text
3. Postscript, PPD=Acrobat Distiller, Output|Colour=In RIP separations, Distiller settings leave colour unchanged - get black-only text
4. Postscript, PPD=Device Independent, Distiller settings leave colour unchanged - get black-only text
5. Export to PDF, Advanced|Colour=Leave Unchanged - get black-only text
6. Export to PDF, Advanced|Colour=CMYK - get black-only text

Rich

[Lou_Dina@adobeforums.com]

Rich, Thanks for the summary. I will keep that one bookmarked, since I have had this problem repeatedly. At least I am aware of it and look for it now in my final check.

Lou

[Gernot_Hoffmann@adobeforums.com]

Rich,

thanks too. IMO only version 3 and version 5 are relevant.
3 for separations, 5 for composite docs. Right ?

Best regards --Gernot Hoffmann

[Bob_Faulkner@adobeforums.com]

Related:

Noticed that if I make an ID doc with a Sheetfed Coated color space, add Swatch Black text, and Export a Print Ready PDF using the Sheetfed Coated profile, I get Black text. Good.

Now, if I do the same thing, only this time select the Incude ICC Profiles checkbox in the Export PDF dialog box, I get 4/c black. Aaugh! Why!

[Jay_Levitt@adobeforums.com]

I'm having the same problem with my Oki 9400dxn. I can have color
management, or I can have true black, but I can't have both. Since the
Oki's magenta is way, way off the chart compared to process, this means
I can't get even slightly realistic color unless I give up black.

As I understand it, ICC profiles can consist of reference points that
map between color space, as well as specific spot colors. I imagine
most ICC profiles contain only the reference points, so that most of the
color translation is approximation and interpolation. I know mine does.

It seems like it should be possible to create a specific spot color
exception in an ICC profile, so that whatever C=0,M=0,Y=0,K=100
translates to in L*a*b should translate back to that. Of course, this
might catch other semi-rich blacks, but if we're lucky you can create a
rich black that's darker.

I downloaded a trial of a profile editor, but was immediately
overwhelmed at all the edit options, and didn't have time to read the
help text - and since it's probably a $600 program I didn't spend a
whole lot of time. Has anyone experimented with this route?

I also know there are places that will create a custom ICC profile for
*your* printer, as opposed to the general printer model, so perhaps they
could do the work.

Thoughts?

--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
[url]http://www.jay.fm[/url] | Why am I in this handbasket?