Re: [Gimp-print-devel] gutenprint 5.0.0.99.1 --disable-nls causes error

[Robert L K. <rl...@al...>]

   Date: Thu, 03 May 2007 10:08:01 -0500
   From: Todd Denniston <Tod...@ss...>
   Cc: gim...@li...

   Robert L Krawitz wrote:
   >    Date: Thu, 19 Apr 2007 17:42:31 -0500
   >    From: Todd Denniston <Tod...@ss...>
   > 

   <SNIP>
   >    P.S. on Letter size in an Epson R800 the cups test page still does
   >    not print the bottom boarder even with A) the driver is not set to
   >    boarderless, and B) configured for "shrink to fit", is this
   >    something you are aware of?  I'll come back to this one later after
   >    doing some more experiments.
   > 
   > I'm not aware of that.

   The cups test page has it's bottom boarder chopped, but other
   applications (mpage||mozilla) print farther out on the paper and do
   not have problems, so I have given up caring about the cups test
   page.  It is too bad that the cups test page(s) do not have a known
   calibration (in inches, cm or mm) for their sizes, shapes and
   boarders. [or perhaps they do, I just have never been able to find
   it.]

I'll try to look at this soon.

   >    P.P.S for a system using cups-1.1.?? is using gutenprint 5.1 a path
   >    that would include retention of sanity ... for both of us?
   > 
   > Should be.
   > 

   I decided to gust go on with 5.0.0.99.1 because it worked well
   enough for me.


   Please provide me with an appropriate clue-by-four about Color
   Models and Ink use.  From experimentation (very much a green shade
   where black should be in CMYK & KCMY) I have come to believe that
   the PPD ColorModel setting should be based on the kind of data the
   user is putting INTO cups/gutenprint, not how the inks will be
   used. This did not seem obvious to me originally and I do not know
   how to help you make it more obvious to others.  Is my belief
   correct about ColorModel referring to input data instead of output
   control?

Yes: ColorModel controls what CUPS sends to Gutenprint.  You shouldn't
use KCMY or CMYK unless your source is CMYK; if you pass RGB data to
CUPS but set the color model to CMYK, CUPS does a canned
transformation from RGB to CMYK, which is unlikely to work well for
any printer and certainly will not work well at all for the R800.

In general, don't use CMYK color model unless you've created a CMYK
output profile against against the driver, paper, and resolution
setting.

   I am now noticing StpInkType/Ink Type, which now seems more likely
   to control ink usage.  with the DefaultStpInkType:None should an
   Epson R800 be using all 7 of it's inks?  and what do the following
   settings mean for an R800 considering there is no Green ink
   cartridge?

It will use CMYKRB when you set the default ink type.  The G stands
for Gloss, not for Green.  It will not use the gloss enhancer unless
you specifically set that option.

You actually shouldn't look at the tag name in the PPD file; it's just
a tag that has no meaning outside Gutenprint.

   CMYKRBG
   CMYRBG
   CMYKG
   RGBG

(which is actually CMY+gloss!)

   and the printer has the following cartridges
   Cart name		expected CMYKRBG meaning
   ____________		___________
   yellow			Y
   magenta			M
   cyan			C
   matte black 		K???
   photo black		K???
   red			R
   blue			B
   gloss			none

   http://gutenprint.sourceforge.net/gutenprint-users-manual.pdf
   section 8.1.3 does not help in understanding.

   The reasons for the questions is that
   A) I am trying to make sure that we are using all the cartridges (it is a 
   waste to put carts in that will only be allowed to dry out) and

You need the cartridge installed anyway -- the printer will not work
without it.

   B) understand why I was seeing a green shimmer in a large section
   of pure black (0,0,0) in an image I produced with gimp that was
   solid blocks of color, even the postscript file when reloaded in
   gimp showed that section as pure black over the whole section,
   i.e., I got the impression that instead of using the black carts
   the printer was mixing colors.

Were you printing in RGB or CMYK color model?  What kind of paper were
you using?