> 1) It is almost as economical to make a unit with 48" tubes. The 24" tubes
> are something of an odd-ball size and in many instances actually cost more
> than the 48" ones.
But for those of us wedging equipment into an already overcrowded studio
four foot bulbs are like 500 pound gorillas, definitely to avoid...
> 2) Electronic ballast is better than magnetic ballast for giving repeteable
> results in exposure. Of course, for really precise work you need a light
> integrator.
And as I have noted (from reading, not experience) the electronic
(digital) ballast makes no heat, reaches temperature instantly without a
warmup period, does not flicker, is easily installed with thumb plug, and
a few other things I forget. However, the catalogs I saw (Motorola and GE)
indicated that the electronic ballast is not available for 24 inch and
only for the T8 (thinner) not the T12 bulbs. But maybe they thought
better of that by now....
> 3) With some of the alternative processes (gum, carbon, and perhaps
> platinum) many on this list have found that the GE Daylight tubes, which
> emit most of their light in the 440 nanometer range (or close thereto) are
> as effective as UV lights at 350 nanometers.....As I recall, the
daylight tubes did
> *not* give good results with cyanotype.
Sandy, I don't know of anyone who found the daylight bulbs preferable for
gum -- they're certainly *much* contrastier, so that any hope of one-coat
gum is ruled out. They also take about 3 times longer, at least with am di
& the mixes I normally use. I've planned to test alternating the BL and DL
bulbs, but haven't yet....
I could not get the DL to expose cyanotype at all.
> seen allow for spacing this tight, so you should consider wiring the whole
> thing with the little bi-pedal tube holders. It is more work, but you can
Sandy, what are "bi-pedal tube holders"?
Cheers,
Judy