Kurt Zimmerman
These notes were written in an attempt to clarify, for myself, the relationship between radiometry and photometry. This clarification is necessary because my raytracer associates a value of radiance with each ray traced, but the illumination community specifies its luminaires according to photometric values. Thus in order to use the value associated with a luminaire sample, I must be able to transform that data into spectral radiance. It should be noted that in the literature the term radiance usually implies spectral radiance. I will attempt to keep the terms separate in this document. I will begin by first defining the radiometric terms then photometric terms according to the ANSI/IES standard[2].
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