Starphire glass & bulb life

From: Judy Seigel ^lt;>
Date: 11/16/05-10:22:19 PM Z
Message-id: <>

About 5 years ago when I broke the cover glass on my plateburner by
dropping something on it from a ladder (accidentally, that is) I replaced
it with Starphire which had been touted on this list -- for about a week.
That is, it wasn't touted for a week, I used it for a week.

But it would NOT print a decent gum, so I stashed the $120 item in the
cellar and replaced it with plain plate for, if memory serves, $25.

The problem was extreme contrast. For what it's worth, I also understand
that, although dichromate is apparently the most sensitive at 360 nm, it
has spikes at other points both above & below. I assume, also, that your
mix, your gum, and your pigment affect those spikes as well.

Exactly why the Starphire gave me only about 3 steps from DMax to white I
don't know, or care... It's also possible that if I'd dinked around with
other mixes & methods I could have improved it, but saw no reason to.

As for speed, not too long after this adventure, I disposed of the plate
burner in favor of the fluorescents... my times for gum there are as
brief as 1 minute (when using a negative that transmits well) to
occasionally 10 minutes with bullet proof neg, usually 3 minutes... I
couldn't cope with faster...

A comment about fluorescent bulbs in particular tho probably all bulbs --
they are extra bright when new; in the first few hours they drop a lot,
then the drop is more gradual over about 9000 hours -- or so it said in
the Westinghouse (or Phillips, or whichever) book. If those BLB bulbs
that took so much longer were very old, compared to very new BL, that
could explain. However, my tests with bulbs of *roughly* same age, showed
the BL about 25% faster than the BLB.

And a comment about washing cyano -- cyano does usually fade to
white or yellow with too long wash... especially if the tap water is
alkaline, which is a cyano bleach.

Received on Wed Nov 16 22:22:28 2005

This archive was generated by hypermail 2.1.8 : 12/01/05-02:04:50 PM Z CST