Anyone seeing display problems with link-placed grayscale images?

[Ann_Shelbourne@adobeforums.com]

I AM placing them in an AI CMYK document.

Making PDFs from Illustrator seems to somewhat inconsistent.

Sometimes I get 4 plates in a composite Acrobat file, unless I select embedded PSD images and go to Filter/Color/Convert to CMYK.

Surely, if theses files are Photoshop GS files, they should pass through Illustrator to a PDF as Grayscales?

Other times, the SAME images, proof in Composite PDFs only as Rich Blacks (whether I use Color / Convert to GS or to CMYK in AI or not!) and the only way to see them as grayscales in Acrobat is to "Print" to a PDF choosing Separations.

[Gary_Newman@adobeforums.com]

If my Illustrator document, containing only a GS image, is in CMYK mode, the saved PDF file will have data in the K plate only, regardless of how that GS image was made.

If my Illustrator document, containing only a GS image, is in RGB mode, the saved PDF file will separate with data in all 4 channels, regardless of how that GS image was made.

If the GS image is somehow converted to an RGB image, and placed or embedded in a CMYK Illustrator file, I’ll get data in all 4 channels, too.

That’s how it’s working for me.

[Ann_Shelbourne@adobeforums.com]

I am totally puzzled then!

My GS files started as RGB files. I have done the conversion in Photoshop CS two ways: Convert to Profile and also using the simple Mode Change.

Seems it might be time to trash all of my Color Settings Prefs.……

[Wade_Zimmerman@adobeforums.com]

I'm with Gary it works for me as well. So did those files I had problems with that time and I am assuming that you are correct and they placed the pdf in Quark which is very confused.

Anyway the GS separates properly from AI.

[Dee Holmes]

Gary, I don't quite understand your 3rd statment,

If the GS image is somehow converted to an RGB image, and placed or embedded in a CMYK Illustrator file, I’ll get data in all 4 channels, too.

Can you explain more simply?

[Gary_Newman@adobeforums.com]

I wondered what would hapen if the Grayscale image were inadvertantly converted back to an RGB file, and placed in an Illustrator CMYK document. So I tried it, and saved out as a PDF to test separations. Just as with the Grayscale image in the Illustrator RGB file, when it got to PDF, there was content in all four channels (CMYK). Which is what I would expect. Separations do not like RGB, no matter where they came from or how they got there.

[Dee Holmes]

Thanx.

[Ann_Shelbourne@adobeforums.com]

But can anyone explain why an RGB file which was converted to GS in Photoshop CS; and then Placed in an Illustrator CS CMYK document (which was originally created as a new CMYK file) is showing data in all four channels when SavedAs a PDF?

This does not happen if you place the same image directly into InDesign CS and make the PDF from there.

[Gary_Newman@adobeforums.com]

And it’s not happening for me with AI CS.

[Wade_Zimmerman@adobeforums.com]

Nit for me as well!

[JasonSmith@adobeforums.com]

In case you missed, Bruce Fraser gives a good explaination in the Photoshop forum.

[Ann_Shelbourne@adobeforums.com]

I have just seen it and am experimenting with it right now!

[Ann_Shelbourne@adobeforums.com]

Mystery solved!

Photoshop-made Grayscales MUST be saved as an EPS.

If you Place a Photoshop GS file, which was saved As a .psd into Illustrator CS, it apparently reverts to an RGB file -- and throws data into ALL channels -- when you make a PDF.

This is BAD.

This does NOT happen in InDesign CS and Illustrator should probably be made to work in the same way as InDesign.

[Gary_Newman@adobeforums.com]

The grayscale files I used - both linked and embedded - that worked fine were PSD files. It only reverts to an RGB file if the Illustrator file is in RGB mode.

[Ann_Shelbourne@adobeforums.com]

Illustrator is DEFINITELY in CMYK mode -- and this set of tests was done in brand new CMYK documents which were Saved As to Acrobat PDFs.

When I used Acrobat 6 Pro's Separation Preview to examine the resulting PDFs:
the files that was made from the AI CS file containing the grayscale EPS shows data in the K plate only;
the files that was made from the AI CS file containing the grayscale PSD shows data in ALL plates.

I now see where this is coming from:
In the PDF dialog, you MUST either use "Illustrator Defaults"
or change the default settings for "Press" in the Compression tab from "Compression=Automatic JPEG" to either "ZIP" or to "None".

If you make your PDFs from Illustrator by "Printing to Adobe PDF", you get the more complete dialog and no pre-set Compression nonsense.

This probably explains why Jason's RIPs were chewing up the gradients when he made PDFs by Saving As from Illustrator, or by Exporting from InDesign, but the problem was solved when he "Printed" to PDF.

So the problem is caused by the "Press" settings Defaults in that dialog box which should be an easy thing to fix in Illustrator 11.0.1.

I hadn't realized it before because I always output PDFs for Press from Indesign -- never directly from Illustrator.

[Wade_Zimmerman@adobeforums.com]

Fraser is mistaken once again about color management, it separates on the black plate only.

Fraser always tries to take the simplistic approach and then attempts to mystify it and as you can see he is doing once again.

He satisfied his audience even if he didn't get it right sand everyone is happy.

[Gary_Newman@adobeforums.com]

Well, I think I’m following you here, Ann, but I’m not sure.

If I do ANY kind of Save As PDF from Illustrator, my resulting PDF file has data only in the K plate. Even using the Press setting with it set to Compression Automatic JPEG. The Compression settings don’t even apply unless your image is over 450 ppi (which is the default, but you can’t change it to anything under 300 ppi).

The only way I can get a PDF with data in the other three plates is if I Print to the Adobe PDF printer, in which case there are no compression controls, and no options for press or web. How is this a more complete dialog? Isn’t it the same as the regular Print dialog?

To me, Save As PDF is much more complete and dependable, and never gives spurious four-channel data for grayscale images.

[Wade_Zimmerman@adobeforums.com]

I am also only getting a black plate it separates fine. I can't help but think that you either have some kind of conflict, ill advised settings or you're doing too much when all you have to do is make a grayscale and place it in an AI document and either print it to separations in AI or save it as a PDF and print it to separation from Acrobat.

I always get one plate and that is the K.

BTW that is how I got the service and printer to understand and output the file correctly I made it black and white. That for some reason they understood.

[Ann_Shelbourne@adobeforums.com]

This is very strange: Gary and I are getting diametrically opposite results.

The Print to Adobe PDF box offers much more flexibility than the Save As PDF box: including an Output tab that permits settings for Seps. or Composite, inks, resolution, media, RR, etc.. None of those can be changed in the Save As to PDF dialog.

And it is definitely the "Press" default compression settings that change my GS images into 4c-process ones. Using "none" or "zip" prevents that from happening.

And Wade, the very reason that your printers had a problem with your file was because they were seeing color info. in what should have been a one-color image. I am sure that the JPEG compression is erroneously generating color (probably RGB) data which screws up the RIP.

I am running Panther 10.3.2 on a G5 but that shouldn't affect the way my PDFs turn out.

[Gary_Newman@adobeforums.com]

I’m in OS 10.2.8 on a dual 1.25 G4, but I doubt that can make a difference in our Save dialogs. Or can it? Where do you have “Print to PDF”? I have no such thing on any menu. I can go to the Print dialog, set the Printer to PDF, and then print and I get a PDF file, but there are no settings for this. Does Panther give you an extra Print to PDF command? I guess I’ll have to try it in Panther later tonight.