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Re: [APML] More bulk TP paranoia

Thanks Don

Your experience (and others) is much appreciated.
I try to hyper film so that I have about 30 days worth in the freezer.
That amounts to about three short rolls with the weather that we have
been having. Sometimes it goes three months before I have a chance to
use it. I have noticed some degradation in that time (might be my
procedures and handling while I bag and freeze). I think I will go the
vacuume bagging route for both the bulk loader and the hypered film.
With 150 foot rolls of TP going for $150-$250 plus shipping from Israel
I don't want to take any chances.

George Anderson
Montreal Canada

Clear skies and good health 

Don Westergren wrote:
> 
> Hi George,
> 
> If you have the vacuum bagging equipment, go ahead and use it.  The hypering
> process both dries the film and replaces the oxygen in the emulsion.  Vacuum
> bagging will help keep both moisture and oxygen out of the film.  Lumicon's
> instructions with their hypering kit suggested keeping the film in the
> vacuum chamber (with a residual of forming gas) for many days at room temp.
> The consensus for using hypered TP is to use it fresh.  The vacuum would
> definitely keep the film fresher, frozen or not.
> 
> I never did get around to testing the storage capability of hypered TP.  I
> remember reading some reports from observatories on hypering TP which said
> that there was a slight measurable loss in sensitivity after storage for
> only 6 days (frozen).  That was back in the late 1980's, and may have
> involved hypering in pure hydrogen rather than forming gas.  I would have to
> dig to find the report again.
> 
> Don
> 
> > Many thanks Kent and Jeff
> >
> > I think that I will go the vacuume bagging and cardboard route. Now i am
> > wondering if I should vacuume bag my hypered TP before freezing.   :^)
> >
> > George Anderson
> > Montreal Canada
> 
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