clipka <ano### [at] anonymousorg> wrote:
>  The problem is that the human eye's sensors for long wavelengths
> (red) are also sensitive to very short wavelengths (violet); thus, when
> translating a very short wavelength to an RGB colour you do get a deal
> of R in there (about 24% of the B channel at 400 nm, at least with the
> table POV-Ray is currently using).

Is this really the eye's sensors?  It seems obvious to me that POV-Ray uses the
color matching function, where the red component does show up in the violet
region.  But this doesn't appear to be reflected in our eye's cone cells;
rather, it seems that the CMF is an outcome of the brain's /interpretation/ of
the signals from the cone cells, or perhaps some preprocessing done in the
retina.

I made this graph a few years ago.  Unfortunately, the source of the data is not
recorded in the scene file; there is a rudimentary comment, but I must have
gotten distracted before completing it.  (Now having flashbacks of a certain
POVer who once posted some of Warp's code without giving him credit.)  I'm
pretty sure it's on my hard disk somewhere, and in any case, such data is
readily available on the Web, at least in normalized form.

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