RE: [APML] Cheap Dessicant to store film with

["Lane, Jason R" <jason.lane@navy.mil>]

Of course it's for fun!  This is great discussion!

What about experiments used for testing a hypered film vs. it's non-hypered counterpart.  Surely someone a while ago had to show that hypered Tech Pan worked better than non-hypered Tech Pan.  Or refridgerated film vs. non refridgerated film.  If my speculative approach isn't the best, then could not those same methodologies be applied to this?  Think also, even if used under many different conditions...hypered Tech Pan is consistently better than non-hypered Tech Pan.  But hypered Tech Pan has already been proven...but at some point it wasn't.

BTW, the fridge is just as bad as the freezer, and the calcium chloride is kept separate from the film cartridges.  I was pretty careful about that.  Don't want dust in my camera.  :)  I'll look into getting silica gel, though.  

Cheers,
Jason

-----Original Message-----
From: astro-photo-bounces@seds.org
[mailto:astro-photo-bounces@seds.org]On Behalf Of Jerry Lodriguss
Sent: Wednesday, August 04, 2004 2:43 PM
To: Discussion of Film Astrophotography; Discussion of Film
Astrophotography
Subject: RE: [APML] Cheap Dessicant to store film with



Hi Jason,

No need to apologize!  This is all just for fun, right!

I'm not sure experience is the best teacher though.  I know I never learn 
from my mistakes. I wish I had had someone to tell me that you can't 
piggyback guide a 12" f/8 Newtonian with a C8 in plywood rings held in 
place with twine.  Sigh. Perhaps we can learn from the experience of 
others.  On the other hand, there are some people who just have to beat 
their heads on the wall for themselves. <G>

If the film you are planning on using for your experiment is the film you 
describe as having frost on the leader, I think you have already screwed 
the pooch. It's compromised before you start.  If you store film in the 
cold, it should be in the refrigerator (not freezer) and it should be 
placed into double, or even triple ziploc bags with silica gel dessicant 
before you put it into the refrigerator.  When you take it out of the 
refrigerator, do not take it out of the bags until the film has reached 
room temperature, or moisture will condense on it, and screw the pooch.

As far as your methodology, here is the dilemma you have... you plan to 
shoot two frames on the same night, one stored with your desiccant and one 
not (the control). The problem is that, unless you buy the control film 
that same day as the test, you have the variability of the storage of the 
control, because as you describe your location, it's humid inside for 
storage and too hot outside.  I guess you could keep both in the 
refrigerator with each individually triple-bagged, but with one with 
desiccant and one without.  But then, you wouldn't know if you got better 
results with the desiccant one if it was because the desiccant one was 
"semi-hypered" (highly unlikely) or because the non-desiccant one was 
degraded.

The other problem you have is that film changes as it ages, so even your 
controls won't match over time... unless you are using a professional 
emulsion that has been stored correctly, and even then.

In any event, my best guess is that the variables will vastly overwhelm any 
chance you have of figuring out exactly what was going on, even if you did 
see some difference. But that is just my two cents, and as far as I am 
concerned, I think they should stop making pennies because they are almost 
worthless. <G>

Using desiccant to store the film in the refrigerator is a very good idea 
(in ziploc bags), but please use silica gel.

Jerry



<snip>
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