U of S | Mailing List Archive | alt-photo-process-l | Re: BL light box 'blues'

Re: BL light box 'blues'

Hi Loris...

I checked out Sandy King's article on introductio to Pyrocat-HD where
I observed
his recommended 2:2:100 (distilled) water to achieve a log density
of .080 - .085 for
VDB.. so the negatives received a developing time of 13 minutes at 73°
They look OK to my eye.... although the 'stain' is not as obvious to
the eye as the stain
I am used to with PMK.

The negatives do not seem to be what one might consider "bulletproof"


On 30-Mar-09, at 3:04 PM, Loris Medici wrote:

Maybe your Pyrocat negatives are way too dense? They can get perfectly
bulletproof negatives (in case of overdevelopment) while they fake
being thin; the brownish stain is a pretty strong UV light blocker!

What film, EI, Pyrocat dilution (A?B?H2O?) and development time (and
regime) have you used for the negatives? Maybe someone with good
experience with Pyrocat may evaluate this info and tell you if you're
indeed overdeveloping the negatives.


30 Mart 2009, Pazartesi, 11:48 pm tarihinde, Ken Sinclair yazmış:
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?


Quando omni flunkus moritati (R. Green)

Quando omni flunkus moritati (R. Green)