From: Sandy King (sanking@clemson.edu)
Date: 11/25/01-06:16:25 PM Z
Hello Jeff
My guess is that you are overexposing your film, and this seems
consistent with your own description of your exposing technique -
"erring on the side of over-exposure." When using a staining
developer like PMK, ABC+ or Pyrocat-HD for platinum printing - or for
most of the alternative processes for that matter - one should avoid
over-exposure like bubonic plague because the extra stain density,
which functions as an actinic filter, will make your exposures
unbearably long.
I use a lot of FP4+, and always develop with rotary processing in
either ABC+ or Pyrocat-HD. For exposure I use an incident system and
meter in the shadows, rating the film at an effective EV of 200. Time
of development varies from about eight minutes for SBR 7 subjects to
about 14 minutes for SBR 5 subjects. If correctly exposed and
developed FP4+ has a very low B+F.
Sandy King
>Hello from Albuquerque NM. This is my first posting to this fine
>list....
>
>I've started doing platinum/palladium. Have done two sessions in my
>newly up and running home rig. I'm excited by the results I'm getting
>but am plagued by preposterously long exposures. Here's what I do: I'm
>shooting FP4+ (5x7 and 8x10) @ EI 64, erring on the side of
>over-exposure. Nothing fancy as to reading; for the time being, to keep
>it simple, I'm just doing split readings (mostly between the darkest and
>lightest readings on the palm of my hand), leaving any particular
>contrast control to the printing stage. I'm developing the film in PMK
>for 12 minutes at 70F. All exposures, regardless. The printing is on
>Platine. I've done a couple prints with pure palladium, a couple with
>about 55/45 Pt to Pd, adding some contrast on one occasion with a small
>amount of sodium dichromate in the pot/oxalate developer. The color and
>contrast need tweaking but I'm happy with both. The exposure times are
>an outrage: From 20 to 80 minutes. I can live with 20, and I
>understand there's only 2 stops difference between that and 80, but most
>the exposures are over 50. The light source is a new "oven" from
>Edwards, which I feel is working correctly. Can anyone tell me if
>anything jumps out of the above procedure as the likely repeat cause of
>these pokey exposures?? I'd sure like to stick with Pyro and know that
>that is the principal culprit. But, you know, if I could just get to
>15-20 minute exposures, I'd be satisfied.... Thank you.
>
>jeff buckels (albuquerque nm)
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