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From: guber@netcom.com (Gordon T. Uber)
Subject: Re: Angstroms to RGB conversion?
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Date: Sun, 2 Apr 1995 04:43:40 GMT
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A. Sprenkle (abs9d@galen.med.Virginia.EDU) wrote:
:  Hi,

: 	I have a very simple need... given a specific
: wavelength in Angstroms or Nanometers, I need to generate a
: color triplet, preferably RGB.


: 	The next step (not so simple) is how to generate an RGB
: triplet based on the relative intensities of several narrowband
: wavelengths..

: 	i.e.  10% Intensity 620nm + 30% Intensity 540nm + 60%
: 700nm = ?R, ?G ?B

: 	Any help would be greatly appreciated.

: 	Thanks Rick

I am not an expert in colorimetry, but basically you use the x, y and z
trichromatic coefficients for a given wavelength to get R, G and B.
See the _Handbook of Chemistry and Physics_. 

For the 2nd step: multiply the x, y and z by the % intensity and
sum.  Normalize the result to x + y + z = 1.00.

Gordon Uber
Palo Alto, CA
