Re: [Gimp-print-devel] Epson Stylus Photo 1270 Paper Margins with 3.1.4.

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

   Date: Tue, 13 Jun 2000 22:55:22 +0100
   From: Ralph Corderoy <ra...@in...>

   I tried -r1440x720, since that's the printer's resolution.  I the same
   image as before, still with some horizontal lines missing, but squashed
   vertically so it only filled the top half of the A4 page.  Was I stupid
   to try this?  :-)

No; it sure would be interesting to know where the bug is there.  My
guess is that it's our bug.

   > > I'd guess that this is because the PostScript is drawing lines with
   > > a line width of zero;  defined to be the thinnest line width the
   > > output device supports.  Perhaps the stp driver is over estimating
   > > how thin this line can be?
   > 
   > It isn't the stp driver; it doesn't know anything about Postscript or
   > line widths.

   OK.  Perhaps the various dithering methods don't work well on very thin
   lines?

I suspect that the problem is that the ink density is so low at high
resolutions that there are simply a lot of dots that just don't get
printed.  At 720x720, the full-dark density is about .6, so most of
the dots do get printed.  At 1440x1440, the density is about .15, so
if you print lines that are one dot wide, you'll lose most of the dots.

-- 
Robert Krawitz <rl...@al...>      http://www.tiac.net/users/rlk/

Tall Clubs International  --  http://www.tall.org/ or 1-888-IM-TALL-2
Member of the League for Programming Freedom -- mail lp...@uu...
Project lead for The Gimp Print --  http://gimp-print.sourceforge.net

"Linux doesn't dictate how I work, I dictate how Linux works."
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