Xerox 8400 printing b+w with colour consumables

Helge Blischke h.blischke at srz.de
Fri May 20 06:01:05 PDT 2005


Anonymous wrote:
> 
> > Anonymous wrote:
> > >
> > > > Anonymous wrote:
> > > > >
> > > > > Hi
> > > > >
> > > > > I'm running a cups server from cups 1.1.22 on Scientific Linux 4 and printing from other linux clients.
> > > > >
> > > > > Our Xerox 8400 color printer (using the Xerox supplied ppd file) is using colour consumables to print most black and white files instead of the
> > > > > black ink consumable.
> > > > >
> > > > > What I'd like to happen is for colour postscript files to print in colour and black and white postscript files to print using the black ink only without the user having to specify whether to print in black and white or colour.
> > > > >
> > > > > I notice that printing plain text files does seem to use only black ink, so the problem seems to be particular to postscript documents.
> > > > >
> > > > > Can anyone suggest how to obtain the desired behaviour for black and white postscript files.
> > > > >
> > > >
> > > > Where do those jobs come from? And could you post (an URL to) a sample
> > > > file? It may be there is a chance
> > > > to print in b/w if the color components (be it RGB or CMY) are all
> > > > equal.
> > > >
> > > > Helge
> > > >
> >
> > >
> > > Helge
> > >
> > > Thanks for your reply. I've put an example file at: http://www-xray.ast.cam.ac.uk/~rmj/pgplot.ps
> > >
> > > That file was made by the pgplot plotting package, but there are also files from dvips that use the colour consumables to render black print.
> > >
> > > Roderick
> >
> > I just downloaded the PPDs for those 8400 printers. It seems that what I
> > suggested in my previous post
> > isn't as easy as I thought (the PPDs already contain a job patch file
> > ....), but using the
> > command line option "-o XRXColor=BW" (without the quotes) or equivalent
> > should switch to b/w
> > printing. Anything else I don't dare to propose as I haven't such a
> > printer at hand to play with.
> >
> > Helge

> 
> Helge
> 
> Thanks, that works, but I was hoping for a way to automatically make the printer not use colour inks for a black and white postscript file.
> 
> Since the printer can print plain text with only the black ink there must be a way for it to know automatically whether to use the colour inks or not.
> 
> I'd be happy to try out any ideas you might have.
> 
> Roderick

>From what I remember from the Xerox web site and from looking ingo the
PPD, the printer seems to follow
the following strategy:
- it assumes that most of the stuff to be printed comes in RGB (as usual
with applications running under
  some flavor of Windows).
- Thus, it will convert RGB colors to CMY colors (ignoring the black
ink), as this conversion is much 
  easier to achieve than taking the black ink inot account and produce
printouts that are similar
  to the average screen display.

If you look into the PPD, you will find several different color
adjustments the user can choose of.
Perhaps you try them out one after the other and see what happens. If
one of these settings matches
your needs (mostly, at least), fix it by activating it within the job
patch file defined in the PPD.

But note, I suspect if you select the BW variant, I suspect the printer
converts colors into 
gray levels unless the PS stream explicitely selects a different color
space.

Helge

-- 
Helge Blischke
Softwareentwicklung
SRZ Berlin | Firmengruppe besscom
http://www.srz.de




More information about the cups mailing list