Re: Wet HIE Film Boxes

["Willem-Jan Markerink" <w.j.markerink@xxxxx>]

On  5 Jan 97 at 0:41, Robert Long wrote:

> 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 think I wasn't clear enough....read on!
 
> |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.  

How there!
Have you any idea how much moisture a human body vents into the air, 
by breathing and sweating? I believe it is close to a liter, if not 
more. Pretty much for a small 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.

Now also note the relative low amount of surface-to-rime-on (I hope 
it is a verb as well, as in Dutch, otherwise substitute with 
sublimation....;-)), in relation with its air content. A film 
cannister has a much higher surface/content ratio (apart from scaling 
ratios!).
 
> |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."

I think the main confusion is that I open my containers and *seal* 
them again after exposure or non-use (can remember the latter ever 
happened though).
Also note that all the rime in your freezer comes from frequently 
opening it up to a fresh supply of relatively humid ambient air.

 
> |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.

I unseal and reseal!
I would never throw bare cartridges back in the freezer. Can't 
believe you trust me to do that....;-))
 
> |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

Not inside resealed containers....8-))
 
> |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.

Opened and closed-again cannisters/containers....;-))
 
> |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.

We sure have to defrost our freezers, but we are not talking about 
the macro climate inside the freezer (with all the air flowing in and 
out), we are talking about a micro climate inside a sealed container. 
And those are safe for refreezing, even after being opened and 
exposed to ambient air (even if that ambient air is quite moist in 
case of dark loading bag).

 
--
Bye,

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      The desire to understand 
is sometimes far less intelligent than
     the inability to understand


<w.j.markerink@xxxxx>
[note: 'a-one' & 'en-el'!]

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Topic No. 4