Overprinting issue

[bogyo.g]

Hello everyone!

I got a PDF from a client, a product catalogue. After printing I realized that some contents (text in headers of each table) disappeared. I checked the PDF, and the text was set to Overprint fill, with process white color.

My Fiery server is set so Adobe PDF Print Engine is active, instead of the RIP.
If in Acrobat the Working Space is set to Coated FOGRA39 (ISO 12647-2:2004), and Adobe PDF Print Engine is active in Fiery, then the text disappears in printing. If Adobe PDF Print Engine is inactive, and the Fiery uses the RIP, then the text does not disappear after printed.

Further more if Working Space in Acrobat is set to  US Web Coated (SWOP) v2, and the Fiery uses Adobe PDF Print Engine instead of RIP, then the text is printed, does not disappear.

Can someone tell me why?

In Acrobar Pro, in the Output preview window, the Simulate Overprinting option is active, then the text disappears. If Simulate Overprinting is inactive, then the text shows. For Simulation Profile I'm using Coated FOGRA39 (ISO 12647-2:2004). But if I change the Simulation Profile to US Web Coated (SWOP) v2 (or any other color space), the text never disappears. Neither if  Simulate Overprinting is active, nor if it's inactive.

Can you please tell me why this is?

Thank you!

[Stephen Marsh]

It's hard to comment on specifics without access to the PDF or inspecting the various RIP settings, apart from general comments. It sounds like the APPE vs. CPSI engines have different default handling of white overprinting.

Are you printing from Acrobat or another app, or do you submit PDF files directly to the Fiery?

If you are not printing spot white, then workflow or preflight software should pick this up before printing. It's then up to you whether you first flag this with the client or just automatically apply a fix to remove the overprint on white.