[argyllcms] Re: camera profiling with newest version of Argyll
- From: Graeme Gill <graeme@xxxxxxxxxxxxx>
- To: argyllcms@xxxxxxxxxxxxx
- Date: Fri, 28 Aug 2015 11:32:58 +1000
Ben Goren wrote:
The first patch has L* a* b* = 96.709 1.8667 -13.059, which is decidedly
I'm not sure where you get that value from - spec2cie says it is
96.694984 -0.854171 0.157998.
(Note that there is a bug in "spec2cie -n" - you can get wrong values out of
fix this in V1.8.1).
I just plotted the spectrum for that patch. It really does look like it's
full of FWA.
But this chart was measured using a ColorMunki - the ColorMunki uses a white
so it has no UV illumination, and won't trigger FWA, even if it were present.
Comparing the spectrum to a reference I have of the ColorCheckerSG measured
Spectrolino, the reflectances look very similar from 420-730 nm, but the
values below 420 are "guestimated", since the illuminant drops off there, and
the diffraction grating looses efficiency.
The A1 white patch D50 L*a*b* comes out at 97.222621 -0.954457 0.777881
for the Spectrolino, and 96.694984 -0.854171 0.157998 for the Munki.
So I think you are on the wrong track.
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