🚀 go-pugleaf

Dov,

Any info is better than none at all, which is what I currently have.
I've read plenty of articles and books on prepress, imagesetters, Postscript, RIPs, etc., and hardly a word about CPSI enters the discussion anywhere. One would think that such an important aspect of what we do would merit more attention and explanation.

I'm using Heidelberg's Signastation imposition software, imposing 4-up signatures from PDF files. It uses an Adobe CPSI 3.015 to parse these documents. it's output on Heidelberg's MetaDimension RIP going to an imagesetter. I'm responsible for everything except the actual file creation.

What I'd like to know, in layman's terms, are the differences between the Adobe CPSI and generic Postscript drivers that, as I
understand it, only interpret Postscript but don't actually rasterize it. I realize that the CPSI has an exponentially higher degree of complexity than, say, a Laserwriter driver going from OSX to a color laser printer. What I'm confused about is how "generic" Postscript is interpreted by such a device and how this compares to a non-generic CPSI.

Is it safe to assume that postscript code for an imagesetter must, by design, have a higher degree of complexity than code for a PS 3 laserprinter? Therefore the CPSI's parser and the RIP perform many tasks with the code that the laserwriter's driver just ignores?

I guess that I've always assumed that color PS 3 laser writers had to have a software RIP built in to rasterize the data. I'm now discovering that isn't the case; that a software RIP isn't necessary to interpret "generic" Postscript. I thought that a RIP was required for any device that interpreted Postscript.

Exactly how does the interpretation of "generic" Postscript differ from a CPSI's interpretation?

I work closely with a designer who uses inDesign 2.02 and loves the Export to PDF option. Everybody loves this option in ID except the people who have to convert them with a CPSI. Sometimes they work fine, other times they fail. When I tell her it fails, I get, "But it printed fine on the Postscript Level 3 laser printer -- so it must be a problem on your end (with the CPSI)." This can be very aggravating, because I don't know how to explain the difference between the two devices in a convincing, logical way.

We have a PDF workflow. I'm well aware that you're supposed to
create a PS file first, then distill from that instead of using ID's "Export to PDF" option. But what do you tell a designer that logically explains why an Adobe CPSI cannot interpret a PDF created by Adobe's flagship products ID and Acrobat? I don't think it's audacious to assume there should be total compatibility between all three -- unless Heidelberg wrote something into their CPSI that, indeed, is upsetting the applecart (or Adobecart).

Invariably, problematic files print just fine on a "generic Postscript" laserwriter PS 3 printer. Designers are using these as proofing devices. So it's frustrating for both of us to parse the same file with an Adobe CPSI and encounter Postscript errors.
No such errors were returned on the laserwriter even when she has "Postscript" (not print-as-image) and "Report PS errors" boxes checked in the Acrobat printer window.

Sorry to be so longwinded. I'm just trying to get a clearer understanding (if that's possible!) of the tools we have to work with every day.