Carl Weese (cjweese@wtco.net)
Wed, 21 Apr 1999 10:07:46 -0400
Matthew,
The graphic arts industry deals with this problem all the time and there
are products to address it....ok, just went over to my darkroom for a
look and the manufacturer is Tetenal, the products are "Anti-Newton
Spray" and "Film Cleaner". The first does what the talc is supposed to
do but in a very controllable (with practice) manner, and the second
obviously is to get rid of the stuff. You can alternately use the spray
on the glass to turn it into a low-cost piece of a-n glass. I would not
use this in the middle of a film-to-film sandwhich because it will
degrade sharpness, but if the problem is happening at the top of the
stack this will fix it.
One other thing: have you said what film you are using? Some films have
lots of "tooth" and won't cause newton rings emulsion to emulsion while
others--most notably TMX-- have very smooth emulsion sides almost
guaranteed to give newton rings in any contact situation. The film with
the roughest surface I know of is BPF 200 so it might be least likely to
have this problem.---Carl
This archive was generated by hypermail 2.0b3 on Thu Oct 28 1999 - 21:39:32