I would like to change a color within a large batch of PDFs.
The color should have been changed in Quark, but now that I'm well into the PDF production cycle, I'm wondering if it's possible to edit the PDF directly.
Apart from color photos, there is only one spot color to be adjusted.
The color in the PDF file is a Pantone color created in Quark. I want to replace it with a different Pantone color. Is that what you mean by an "arbitrary replacement"?
The entire document is black and white plus this color. The file was exported as a composite process black plus a spot color.
I can open the PDF as a text file and I see that "CustomColors: (PANTONE 267 C)" appears twice, as does "CMYKCustomColor: .842 .987 .002 0 (PANTONE 267 C)" but replacing them with their counterparts in a document that is the same except for a different spot color has no effect.
If the spot plate has any tint below 100% you can't replace it in any automated way using out-of-the-box Adobe software.