[argyllcms] Re: rgb output profiling

  • From: Graeme Gill <graeme@xxxxxxxxxxxxx>
  • To: argyllcms@xxxxxxxxxxxxx
  • Date: Thu, 23 Nov 2006 16:06:15 +1100

regarding output profiling of printers with rgb profiles we are generating a 
target with
the standard flags without adding iterative & adaptive full spread patches.

What is the command line you're using ?

we have made some tests adding such patches, but so far we do not see any 
advantage yet.

Just because options are present, doesn't mean you have to use them...

first of all we'd like to ask if you can give us some more detailed information 
the - f flag (-t, -r, -R, -q -i, -I) as we do not exactly know in what logic 
> flags will add patches to the regular grid distribution of the target 

I really don't recommend a regular grid. It's inefficient, and can tweak
resonance's in the per channel curve fitting. Instead, use the recommended
settings <http://www.argyllcms.com/doc/Scenarios.html#PP2>. This gives
you a set of test points at the colorant extreme combinations (that's what the
default -m value of 2 gives you), and the -f gives you the balance of the test
points using the default Optimized Farthest Point Sampling.

the second question we have; is it possible to add single patches into a ti1 
we would like to add patches such as rgb (0,0,1 ; 0,1,0, ; 1,0,0 ; etc.) to 
dark areas for instance...

You get the patches in your examples by default due to -m2. You can add other
things like wedges (-s and -g) which is good when you're profiling a source
space, and you can edit the .ti1 file and add extra specific colors
if you like too (also good for characterizing proofing source spaces.)

You can use the -r flag in printtarg to avoid randomizing the patch
locations, and then preview the result with something like PhotoShop
or Ghostscript.

Graeme Gill.

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