Freezing motion picture film

Diana Ruby-Sanderson <dlrs [at] rmh__com> writes

>I recently completed a survey of our film collection using the
>testing strips from IPI that measure the presence of vinegar
>syndrome.
>...
>Since we have no funds with which to pay for the transfer to new
>stock or clean the existing film, we're going to have to freeze the
>the worst of the bunch.

I would not recommend that you freeze the film on metal reels at
all--the film should be put on film core's for storage.

I am also not sure that I agree with your plan to freeze films with
advanced vinegar syndrome.  The idea behind freezing is to "buy
time" and slow down deterioration.  If you have materials that are
already in a severe state of deterioration than these films must be
copied now. If they are important materials and you have no money it
would be responsible to give them to an organization that can
properly care for them.  Perhaps you can work out a deal whereby you
get a VHS viewing cassette in exchange for their taking care of them
and copying them to film for preservation.

As far as the freezer goes a *very* important aspect is humidity
control  and specifically *low* humidity--and most freezers of the
type you are speaking of have no humidity control at all in addition
to having mediocre temperature control which will cause temperature
cycling.  It *may* be possible to reduce humidity of the film in the
bag before freezing using a desiccant.  This type of encapsulation
can be a bit controversial because you have created a
micro-environment--and so when you defrost the materials to
acclimate them for use at some point this needs to be done with
extreme care.

There may also be other issues specifically associated with
micro-environments with a high level of acid as you indicate.  The
wizard of things of this sort is Doug Nishimura at the Image
Permanence Institute in Rochester.  I suggest you have a long
conversation with him.  I believe that there is a vendor that sells
bags with a good humidistatic barrier and a "system" for freezing
this way but I believe the system is primarily designed for
photographic materials, perhaps it can be modified.  I believe Henry
Wilhelm is familiar with this system.

Jim Lindner
VidiPax
The Full Service Magnetic Media Restoration Company
212-563-1999 ext. 102

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                  Conservation DistList Instance 12:29
                Distributed: Tuesday, September 22, 1998
                       Message Id: cdl-12-29-005
                                  ***