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Color temp puzzle





Mike Reichel replies;
 

>So the answer then would be to use a spectroradiometer as suggested by the CIE
>instead of a colortemperature meter? "

Yepp, but I call it a spectrophotometer (as does JS).
 
>See, the goal is this.  I would like a white field on the monitor, both SGI and
>regular Video/RGB/NTSC to "look/feel" the same as my surrounding lightsources,
>as well for example a filmscreen...


Cant do it. As John Sprung pointed out as well as implied by J Hardis, the spectral distribution is known on things that glow. Indeed the CIE uses the Planckian radiator to create that shade of white we see on the diagram and it conveys how the peakpoint (dominant wavelength) on the glowing object moves along as its temperature increases, hence colour temperature. Sources that emit light like a flourescent do this by excitation of electrons that when falling back into their resting levels then give back the energy in the form of some light. Very often it is invisible UV light and to see it a phospor is used. Spectral distribution here has no resemblance to incandescent (glowing sources). Thus trying to do a full spectral match with another source is not doable.

But John (Sprung) does the Sun glow? Does a thermonuclear reaction produces a Planckian locus?
 
Mike Reichel

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