Re: [APML] Cheap Dessicant to store film with

["Don Westergren" <westergren@netzero.net>]

Jason,

You have heard from a lot of APML's expertise.  The messages from Kent,
Jerry, and others are true about hypering being a lot more than control of
humidity.  I did some comprehensive film tests a few years ago that included
one test that is not  reported in my film test data, see
http://home.nethere.net/mpd/FilmTestData/FilmTestData.htm

Here is a data point to consider.  At the request of a member of APML, I
tested unhypered "Old RG200" by drying it through the normal hypering
process, without the forming gas.  That is, I put the film in a vacuum
(about 28 in Hg) at 50°C for 12 hours.  The film response was exactly like
unhypered film - NO HYPERING EFFECT.  The Old RG200 was a film that really
needed hypering for astrophotography, and in my estimation it was the BEST
color negative astro film there ever was.  Of course it's gone now.

The one film available now that needs and works with hypering is Tech Pan.
None of the currently available color negative films have been shown to
benefit from hypering.  Notice how I hedge my words here.  There may be a
film that hypering makes into a good astro film, but the APML (and I) don't
know about it.  If anyone thinks they have found a film that works, please
let us know.  Every one of us want the best films available.  An example of
that is Konica Centuria (and Super Centuria) 400 that was recently
identified as a very usable astro film.  I'm not aware of any test data for
the Konica film that shows the effects of hypering.

Don


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