Originally Posted by sotti
I put one on order so I can put a meter to it.
Also when I walked into the cal lab today I noticed it was litered with CCFL daylight bulbs, although we were doing CRI testing on them, I'm having them checked for chromaticity.
Great! I'll be curious to see your results, esp. on the GE daylight CFLs.
The bulbs change color slightly as they warm up btw. In my tests, they appeared slightly redder in color when "cold" (ie just turned on) versus after some warm-up time. And it appeared to take about 10-15 minutes before they "settled in" to a fairly constant color (which I'm guessin is typical for fluorescents).
Not sure what the normal procedure is for reading bulbs, but it might be interesting to see both a "cold" (just on) and "warm" (on 15 minutes or so) color reading, to see the difference.
My guess is the tech at GE simply looked up D65 and reported it back to you with out any data.
Possible, but I was pretty explicite in my request, and gave them the model # of the daylight CFL bulb, etc. So I'd give them a bit more credit than that. I believe GE lists CIE coordinates for some of their other industrial bulbs, so they probably just needed to dig around a little for info on the tri-phosphor daylight bulbs. Probably not the sort of request they get too often on their consumer products.
The CIE values they sent me (x=0.313, y=0.337) are also not a precise match to D65
(x=0.3127, y=0.3290). If the values they gave me are correct, then the bulbs should be a hair off D65 towards green. (There are couple suggestions on how to compensate for that here