Same as always: use a profile that maps 100% black (RGB, LAB, whatever) to 100% black ink, or separate your photos and text differently.
Photoshop’s default profiles are setup for photographs (where a rich black is desirable), not line art and text (where you may or may not want a rich black).
Command+Shift+K (Color Settings)
Working CMYK: (enter a new default profile)
or
Edit> Convert to Profile: (the desired CMYK profile)
I don’t know which CMYK profile would maps 100% black (RGB, LAB, whatever) to 100% black ink
On the OP, I would generally prefer to take the PDF into Acrobat Pro, apply the transparency flattener with the outline text option so that fonts become vector paths and then open the file into Illustrator if required. I hate to rasterize when I don’t need to (even more so at lower than output device resolutions for text).
As for profiles…
I don’t know of any Adobe supplied or other profile that will map only to the K plate of a CMYK file.
I think that the often scorned legacy Custom CMYK interface is (99%) capable of doing this [max gcr + 100k limit] and any scum dots that may be left under the K elements can be fixed in a number of ways. Of course, images will also separate with this GCR, which may not be good.
Every time that I dive into Custom CMYK, I wish that Adobe would offer something similar (or perhaps like the old Imation CFM), that worked with ICC profiles. Even if the ICC profiles were only ones blessed by Adobe and not any custom made ICC profile, that would be a start.
Of course, the other option is to wait for somebody to create and freely distribute ICC profiles made from standard measurements with different separation variables for those that understand what they are doing (total ink, TVI, GCR/UCR curve, black start/end, UCA). A one size fits all profile is not enough for those that are serious about press work.
Sincerely,
Stephen Marsh
