InDesign CS3 creates 4C crop marks???

[Tech]

This is rather strange for a 2-color layout (black + spot). This doesn't happen often but when it does, it's usually when some Illustrator files are link the layout. Color separation doesn't show any 4-color usage anywhere on the plate except crop marks, page info, and of course, registration marks is selected.

What is the best way to resolve this or leave it since it won't get printed anyway?

 

[GinSu]

Printing Trumps PDFing (sometimes)

Printing Trumps PDFing (sometimes)

There is probably a CMYK image in the placed AI file. InDesign can't determine wether the CMY plates from the image are blank or not so it prints them. The only way I know around this is to print only the desired separations, but if you're PDFing then you'll have to control the separations with your RIP.

In the old days, we had to have a CMYK trigger to force process colors to print when using OPI/FPO images, my how things have changed in the last 20 years!