Re: Wet HIE Film Boxes

[boblong@xxxxxxxxxxx (Robert Long)]

On Sat, 04 Jan 1997 19:39:13 +0000 (GMT), Willem-Jan Markerink
<w.j.markerink@xxxxx> wrote:

|Sorry to pick on this again Robert, but cold temperatures only do not=20
|cause excessive condensation/sublimation.

No, of course they don't.  It requires humidity as well.  What your
discussions of the subject consistently ignore is the tendency of
humiditity to wick and equalize, given the opportunity.  In a sealed
container it is not given that opportunity, so if the container is
cooled to below the dew point of its trapped atmosphere the result
will inevitably be condensation.

|I thought long and deep for a good example, the best one I could=20
|think of is when you park a warm car out in a cold freezing night.
|All frost ('ripe'?) is formed on the outside, never on the inside,=20

Um...well, it's "rime."  But yes it can form on the inside, too
depending on the humidity trapped inside, and no it doesn't require "a
bunch of warm sweating people" inside the car.  On cold mornings, for
example, there is frost on the *inside* of the storm windows in my
bedroom.  Granted that when people are exhaling warm, humid breath
within a cold car, the frost will form very much readily on the
inside.  And granted that if the temperature is dropping slowly past
the dew point, the interior of the car will consistently be somewhat
warmer than the exterior, keeping the interior frost-free while frost
is forming on the exterior.  But the fact remains that it can form on
the inside, and it can do so without anybody inside the car.

|there for years. None of it ever got wet at all.

If you have broken the inner seals and allowed room moisture in, I
cannot believe that the outside, at least of the cassettes haven't
received frost just as the inside of your freezer does when the
moisture from the room condenses and freezes after the door is closed.
All the film boxes that I have stored in the freezer show the effects
of condensed moisture.  Those nearest the outer side of the door show
the greatest, while those nearest the hinge (all are stored in the
door racks) show the least, but none is free from this apparent
"wetting."

|Again: real nasty condensation only happens with a steady supply of=20
|air, which dew point is higher than the cold object you are putting=20
|into it. A sealed container will not create nasty condensation.

A *sealed* container will be frost-free, of course--as long as its
relative humiditity and thus its dew point is sufficiently low when it
is sealed.  I've never said otherwise.  You seem to be saying that you
unseal your containers and the film still doesn't suffer from frost,
which I find unbelievable, frankly.

|Heck, I would otherwise even get problems when dark loading and=20
|changing HIE while skiing. It can get pretty damp in such a=20
|changing bag, and you do seal the exposed film with quite damp air,=20
|while it very likely faces sub zero temperatures again (I went close=20
|to -20C this year, with a gnarly stormy wind on top of that....never=20
|had to whack my fingers as hard as this winter to get blood back in=20
|after a few minutes of shooting....<shrugg>....I only hope those=20
|shots were worth the torture....8-))

I'm sorry, Willem, but this just reads like sheer nonsense to me.
Again, it ignores the tendency of atmospheric moisture to equalize. =20

|I have thrown opened cannisters back in the freezer as well....8-))

In that case, you're obviously asking for trouble.  Again, because of
the tendency of atmospheric moisture to equalize--and to condense out
on the *first* sub-dew-point surface it encounters, you may not yet
have had any trouble with the film itself due to condensation or
frost.  But you can't be sure you won't if you continue to do that.

|I also can't believe that Ektachrome IR is never thrown back into the=20
|freezer, whereas it needs -18 to -23C as unexposed film (the color=20

As I've said before, you have convinced me that sealed, unexposed film
isn't damaged by refreezing, and I've refrozen some films myself since
our earlier discussion.

Perhaps Holland is much drier than the Eastern Seabord states.  If you
never have to defrost your freezers and refrigerators, this must be
so.  But if you do have to defrost them from time to time, then it
seems mainfest to me that you are playing with--well, ice, not
fire--in putting unsealed film into the freezer.  Without knowing the
dewpoint within the cassette, the rate of cooling within the cassette,
and the rate at which the dewpoint is dropping as moisture excapes
through the cracks, you have no way of being sure what will happen.

Bob Long
(boblong@xxxxxxxxxxx)

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Topic No. 2