[Openicc] colord Printing Plans

[Graeme Gill]

Chris Murphy wrote:
> Color managing PostScript, yeah, if you have knowledge and control about how the device
> behaves. I assume you've talked to manufacturers about how their own printers function
> and what crap responses you get from them, like they really have no idea how the
> interpreter is working in the printer.

It depends what level things are operating on. Typically a print driver will
drive the printer natively (ie. CMYK, lclmCMYK etc.), so the color behaviour
has to be defined by the driver/RIP anyway. For printers that don't have
an accessible native mode, the option for a print server are to try and
run with the printer PDL, which can lead to all sort of compatibility problems
and special cases as well as poor color management, or to RIP into the printers
PDL. The latter can be rather slow though, if you resort to sending rasters
rather than keeping it higher level PDL.

> The problem with RGB PostScript is that the printer itself is going to make an
> assumption for the incoming RGB and convert to CMYK. I have had printers ignore
> embedded CSAs in incoming PostScript and only use internal CSAs. I've had them ignore
> only CRDs in the PostScript, but honor CSAs. I've had them ignore both. I've had them
> honor both. The only way you know WTF the printer does is to test it because the
> documentation for the printers sucks. And the manufacturer's tech support sucks even
> worse.

Sure. If you are at the mercy of a RIP built into a printer, you have to figure
out what it does and how to manage it. Note of that is clean or easy.

Graeme Gill.