[argyllcms] Re: Calibrator correction for Eye One Display 2 & GB-LED Backlight LCD Monitor?

  • From: Milan Knížek <knizek.confy@xxxxxxxxx>
  • To: argyllcms@xxxxxxxxxxxxx
  • Date: Thu, 31 Jul 2014 23:23:26 +0200

Thanks for the clarification. Seems to work quite fine, as far as my
eyes can tell... (Definitely no visible colour shift as it appeared w/o
the correction matrix.)

I am about to buy ColorMunki Design soon and plan to re-do the
correction matrix to see how off the use of fakeread with sRGB emulation
of my monitor was.

Milan

Graeme Gill píše v St 30. 07. 2014 v 23:03 +1000:
> Milan Knížek wrote:
> 
> > x "fakeread values are normalised to 100"
> > 
> > x meaning that dispread values are not normalised to 100
> 
> Hi,
>       actually with the current code dispread can return either
> normalized (default) or non-normalized values (-w flag).
> This is marked in the resulting .ti3 by the
> NORMALIZED_TO_Y_100 YES/NO value.
> 
> > My confusion stems from the test.ti3 (produced by dispread), which reads
> > that the numbers _are_ normalised:
> > 
> > KEYWORD "LUMINANCE_XYZ_CDM2"
> > LUMINANCE_XYZ_CDM2 "66.758160 61.640342 95.172183"
> > KEYWORD "NORMALIZED_TO_Y_100"
> > NORMALIZED_TO_Y_100 "YES"
> 
> ccxmake will take either case and restore the absolute
> values for computing the correction matrix.
> 
> Since the fakeread output doesn't have the information
> needed for this to happen, you would have to add this,
> by adding the LUMINANCE_XYZ_CDM2 value and
> NORMALIZED_TO_Y_100 "YES" so that it too can be
> converted back to absolute by ccxxmake.
> 
> > Is your hint re. copying of LUMINANCE_XYZ_CDM2 values from test.ti3 to
> > ref.ti3 still valid nowadays?
> 
> Yes, since I haven't added the code to fakeread to read the ICC
> SigLuminanceTag and use that to set a LUMINANCE_XYZ_CDM2 value,
> even if it is present in the profile.
> 
> > BTW, my vendor tailored Huey for Samsung SyncMaster XL20 seems broken
> > (all of sudden there is too much green after calibration), hence I had a
> > similar idea as the original poster to re-use my Eye-one Display 2 and
> > rely on Samsung's emulated sRGB to create the correction matrix.
> 
> Hmm. Either something has gone wrong with it electrically, or
> the filters have aged.
> 
> Graeme Gill.
> 
> 


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