>Can somebody confirm this is 24 inch 40 watts? Is there a 240 volt
>equivalent? Can anybody else from 240 voltland suggest an alternative?
I have an eponymous answer for him, from what-is-now-slightly-less-than-240
I don't know if Philips Electrical Ltd., (Lighting Division) has outlets in
the Antipodes, but I have an (admittedly out of date) UK catalogue
describing series of long wave UV fluorescent lamps intended for printing
and copying purposes; in particular their "Actinic 05" series, which peaks
around 370 nm, includes a 40 watt 600 mm (2 ft) model - number MCFE 40W/05
with bi-pin cap.
There is also a series "Actinic 03" peaking around 420 nm, if anyone
prefers it. Recent posts have stated that this is the optimum wavelength to
use, but I wonder where the evidence for this notion comes from.
Both iron-based sensitizers and dichromated colloids are most sensitive at
365 nm, or thereabouts, although the sensitivity of dichromate does extend
further into the visible region than does that of ferrioxalate.*
Which raises another point evident from some recent postings: why use
"Black Light" tubes (by which, I assume, is meant those with black glass
envelopes to filter out all the visible radiation)? Unless BL tubes are
much cheaper, it seems a pity to absorb all those useful photons.
*see Jaromir Kosar, 'Light Sensitive Systems', (Wiley 1965) pp 71-74; and
yours truly, The Journal of Photographic Science, vol 34 (1986) p 15.