[plug] Grayscale printing

[Mike Holland]

Adam Davin wrote:
> Hello all, 
> 
> I have been googling for this for a while and not come up with anything
> helpful.
> 
> I am want to be able to force colour documents to grayscale and cannot
> find (if one even exists) a '-o' lp option that allows this. I am
> printing to an "Epson ALC 1900" colour laser printer using cups with the
> Epson ALC1900 ppd file. Is there any way I can do a:
> 
> lp -s -dEpsonALC1900 /path/to/document.pdf -o something=force-grayscale

try "foomatic-rip -P <printer> -o docs <file>" | lpr,
as in the foomatic man page to print a list of options from your PPD 
file. Or just grep the .ppd for -i gr[ae]y.
Some printers seem to have a way there to force grayscale.

It's printer dependent though, so if you find a general answer that
tells ghostscript to generate gray, from the lpr command line, please
let us know.