Silver sensitization w/ NH3?
Tox Gunn (tox@remarque.berkeley.edu)
Tue, 24 Sep 96 12:20:48 PDT
I was talking with my martial arts professor recently, and he noticed that
I'd stashed several boxes of 4x5 in the fridge. The conversation turned to
photo-related topics, as he had done some press coverage in the 50s/60s.
What aroused my curiousity was something he had mentioned about sensitizing
roll film w/ ammonia vapor treatment (about 12 hours) immediately before
shooting the stock. From his description, it sounds like he was getting about
a 2 stop increase in film sensitivity (as opposed to pushing it afterwards).
I thought I'd be more likely to find info here than on the stock photo
groups.
Has anyone else heard of this technique? How effective is it? It strikes me
as something that could be used to selectively boost the sensitivity of areas
of sheet film, almost like burning before the exposure.
Curious,
Tox
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* Tox Gunn .......tox@remarque.berkeley.edu *
* "Your sanity is not my responsibility!" *
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