[Openicc] Drop size calibration

[Robert Krawitz]

   Date: Tue, 29 Jan 2008 07:58:01 +1100
   From: Graeme Gill <graeme at argyllcms.com>

   Robert Krawitz wrote:

   > This tuning is on a per-printer, per-drop size basis; it doesn't
   > involve actually modifying the dither algorithm.
   > 
   > The other thing is that I suspect that not every combination of
   > printer, paper, resolution, etc. will wind up getting properly
   > linearized, so I want to have reasonably good estimates of the drop
   > size out of the box.  I could always simply set sizes of 0.25, 0.5,
   > 1.0 for everything and be done with it, but then a lot of resolutions
   > on a lot of printers will look rather ugly until someone gets around
   > to doing a lot of work.  This method is a lot faster than what I was
   > doing before (when I had to recompile the driver and print a whole
   > bunch of test strips and then try to estimate matches to make any
   > changes at all to the drop sizes).

   If this is the situation, then yes, allowing for the different dot
   sizes this way seems to be pretty efficient. The color quality gap
   between a printer that is controlled this way, and one that has
   been calibrated and profiled is likely to be enormous though.

   While it's impossible for any vendor of printing devices/software
   to calibrate and profile every possible combination of mode and
   media, there's an expectation now that at least a useful set of
   such calibrations and profiles will be provided as a fallback.

And that's exactly it -- these defaults that I'm generating will
hopefully provide the basic default settings for
printers/resolutions/page sizes that aren't calibrated and profiled.
The results won't be as good as results that have been more accurately
measured, but they will be good enough for most purposes.  Selecting
arbitrary drop sizes, with no attempt at calibration, will yield
inferior default results.

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

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