gabrielma said:
My B&W image was shot on C-41, and it's purple on my book copy.
I was in the printing industry, so let me give it a try...
General Printing use CMYK, not RGB to mix a colour range.
If it is a true grey scale image, and if the printer use digitial workflow aka CTP (Computer to Plate), then that area should only be in the K zine plate (Black).
There should be nothing in any other plates.
So, since there are only K ink (Black), there are no other ink to mix any colour.
Joe, Did you send the files in CMYK or in RGB format?
(again, with CTP) A print have to convert any RGB files to CMYK files, so they can seperate it, into a file for the C plate, M plate etc...
If they are converted, there are always some issues, but mostly concern with colour, ie, what came out in CMYK (digitial proofing or manually printed proofing, with actual zine plate; or production prints) might not match RGB proofings.
Cheers
Will