I am having really major difficulties in finding GE SPX-50 lamps or
equivalents (36" and 48") in my area, and I have temporarily equipped my T-8
fixtures with CW tubes. When initially installed, they seemed quite bright
to me, but also unpleasantly yellowish. After two months of use however, the
color of the light seems a little less unnatural, and I am wondering if it
is an adjustment of the emission spectrum of the tubes after the initial
break-in period, or if it is that I am just getting used to it. Does anyone
know if the color temperature of a tube (specifically, T-8 CW) changes over
time? I have now resorted to a mail-order company ("Bulb-man" 1-800-6481163
in Nevada, what a name!) which should ship to me some F32T8 tubes 5700K with
a CRI greater than 90.  No three-footers available anyway, and good-bye to
the economical advantages of lamp cost of T-8s versus some of the brighter
T-12s! Please just do not tell me to go to Grainger, since they do not sell
to private customers without a business account. Is there anyone in the
North Jersey tri-state area interested in buying and sharing a whole case of
5000k 3-foot T-8s? Some electrical supply stores seem available to order
daylight lamps by the case only.