[Openicc] [Gimp-print-devel] Drop size calibration

[Robert Krawitz]

   Date: Sun, 27 Jan 2008 17:37:23 -0800
   From: "Roy Harrington" <roy at harrington.com>

   As far as I can tell your method is matching the density of a 10%
   large dot with say a 20% small dot.  But in a real print the
   transition from small dot to large dot happens at a much higher
   percentage -- say 100% small to 50% large.  So while it would seem
   that mathematically its the same thing, the non-linearity of dot
   gain makes a difference.  Small dots have more relative dot gain
   than larger dots because the circumference to area ratio is larger.
   I suspect this is a least one factor causing your "larger" small
   dots.

   I think you can use the same idea but make the constant strip 100%
   small dot and the gradient strip the large dot.  This is basically
   what I measure.  I like your idea about making the different ranges
   for each dot size, I may have to try something similar.  (I've been
   using an environment variable to force single dots but this
   requires 3 print jobs not 1).

I'll have to give that a try.

-- 
Robert Krawitz                                     <rlk at alum.mit.edu>

Tall Clubs International  --  http://www.tall.org/ or 1-888-IM-TALL-2
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