Re: BL light box 'blues'
Ken,
Pyro negs, as well as Tmax 100 film, do not work for UV processes...the
other problem I had with this mysterious long exposure thingy with students
was UV blocking glass in the contact frames. Third, in the winter with
really low humidity I find that my exposure time is affected. But with BL
bulbs even with my longest exposure with 1A:1B it is 24 minutes; 2A:1B is
half that. Longest exposure, on Fabriano AEW paper which hates cyano...
Chris
PS SO fun being in Dallas and had dinner with Eric Neilsen, Melody Bostick,
and Tillman Crane--Jeremy Moore where were you?????? We had FUN shootin'
the breeze about photo!
----- Original Message -----
From: "Ken Sinclair" <photo1@telusplanet.net>
To: <alt-photo-process-l@usask.ca>
Sent: Monday, March 30, 2009 3:48 PM
Subject: BL light box 'blues'
Have recently decided to intensify my interest in non-silver, I
constructed my
new UV light-box using 10 BL tubes presently 5 inches above my printing
frame.
So that I could use the same negatives for both silver-gelatin, Cyanos
and VDB
I switched to Pyrocat as a developer... and I must admit, they do look
"sweet".
A few years ago my southern Alberta summer sunlight exposures for Cyanos
were
running around the eight minute mark... which expanded to around two and
a half
hours in the rather weak December sun.
The exposure times I expected using the new 24" BL tubes are nowhere as
short as I had
hoped... Cyanotypes seem to be requiring around 40 to 50 minutes while I
have not
yet reached the 'end-point' for acceptable VDB exposures, it seems as if
60 -70 minutes
might be the absolute minimum.
I do not have a stouffer wedge to assist reaching my standard exposure
times, my patience is
wearing (as my frustration level rises).
I have just put a VDB out on the deck to enjoy some natural UV rays from
the sun
for a time comparison...
Are my BL light-box test exposure times "out of line" with times
experienced by others?
Ken
Quando omni flunkus moritati (R. Green)