RE: theoretical gum question
Paul, my current procedures seem to be able to give nice / rich / long range casein prints in just 2-3 layers with negatives of density range log 1.1 - less than what I use for gum and I think I need to further reduce this to maybe log 1.0 or 0.9... Dichromate strength is 5% or 2.5%, exposure time 30-45 *seconds* under a bank of 8 40W UVBL bulbs. Conceptually they're pretty close (I mean casein and gum) but, IME, practically they're very different. (At least with my coating solutions, maybe I'm off by a magnitude!?? Anyway, I don't care, I think I like what I get... Will share the results later, I'm pretty busy right now at work + a workshop preparation.) -----Original Message----- From: Paul Viapiano [mailto:viapiano@pacbell.net] Sent: Thursday, September 10, 2009 10:19 AM To: alt-photo-process-l@usask.ca Subject: Re: theoretical gum question Thanks, Loris, Phritz and Katharine... I started thinking about this after reading the Lukas Werth article in PF, in which he uses pt/pd-range pyro negs for his casein printing. I know casein is not gum, but reading about him doing up to 10 layers and getting this beautiful long-range print had me daydreaming ;-) Katharine, when you say they don't look as clean and crisp, do you think that has to do with the contrast? Paul
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