At 07:38 PM 3 March 2002 -0500, James R. Frysinger wrote: >The candela *is* photometrically related. Its definition is absolute >only at one frequency (corresponding to ~555 nm in free space). For >other frequencies, the luminous efficiency function is used. The CIE >standard luminous efficiency function is photonic (daylight).
I am going to forward this post to the "expert" who told me otherwise and see what he says. He is an electro-optical engineer in far-infrared (cryogenic) radiometry and interferometry, so obviously does not use photonic units directly. So I suspect that he fed me bad info -- thanks to Jim F. for correcting me. Jim, it appears to me that you consider "photometric" and "photonic" to mean the same thing -- is that correct? Also, do you concur with my "expert" in saying that nits are used because displays are distributed rather than point light sources? Jim Elwell
