"Cousin Ricky" <rickysttATyahooDOTcom> wrote:
> Mike Horvath <mik### [at] gmailcom> wrote:
> > On 11/22/2015 4:22 PM, Alain wrote:
> >  > You may try to use rgb instead of srgb.
> >  > If the original render used assumed_gamma 1 and uncorrected rgb values,
> >  > then, using srgb would give incorrect results.
> >
> >
> > Well, the colors are supposed to be exact values using Lightsys. I want
> > to get them physically correct.
>
> Alain is correct.  CIE.inc was written years before the srgb keyword was
> introduced to the POV-Ray 3.7 betas, and was designed for proper use without it,
> using assumed_gamma 1.0.  You already use assumed_gamma 1.0 in this draft, as
> well as in v1.0 of this module (although the included illustration is washed out
> for some reason unknown to me).  The srgb keyword was intended for color values
> from outside sources.  By using it on CIE.inc-generated values, you're just
> messing up what was already physically correct.
>

The original image looks a bit washed out to me, too (although I don't have a
true Munsell color wheel to look at.) I have an idea about why that might be so
(and about why the new 3.7 render looks more saturated, but *possibly* still
incorrect) Just a guess: I assume the original render was done in v3.6xx. *If*
it was rendered with an assumed-Gamma of 1.0 instead of 2.2, then the color
values you chose to use may have been 'gamma-lightened' incorrectly there;
whereas the newer render in 3.7, although set up correctly in the SDL with
#version 3.7 and assumed-gamma 1.0, may itself be doing some gamma-fudging
because of the original color values that were used. Hmm, sounds complicated!
;-)

Over and above all this, my own eyes (and CRT monitor) tell me that there's
something not-quite-right about the *greens* in both images; they look a bit
'olive'-colored to me. That's just a subjective assessment, of course, but I
wonder if anyone else sees it that way?

Something else I noticed: There seem to be shadows falling on some of the color
blocks, at least in the *original* image; perhaps that effect is producing a
somewhat false impression of the colors. Maybe a shadowless light would help(?)

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