[LargeFormat] Polaroid in cold

[TigerShark]

I would say that in colder weather shutters tend to get sluggish, hence a
1/60 exposure may effectively be a as low as 1/30 (or even 1/15), hence your
effective ISO speed would go up, in those terms, while your Polaroid speed
will go down because of sluggish development.  The best is to test the
shutter with a shutterspeed tester in the conditions you are working in.
Calumet makes one for about $70 or so.

The speed of the Pol film really depends on process temp and not on the temp
it was exposed at.  A simple test would tell you how process temp really
affects the speed.  The table in the box is just a guide line and process
under 60 degrees F seem to give bad blotchy polaroids, never mind how long
you develop.

I like (and use) the under shirt process and it works fine.  Just dont leave
the polaroid any longer in the back than necessary, since the thing is
freezing cold too.  Fast work really helps to keep exposure to the cold at a
minimum.  Camera ready, shutter closed and cocked, insert warm polaroid in
(warm) holder if possible, insert in camera, pull, expose, push in, remove
holder, pull film in process setting, and back under shirt.  At 0 degrees
this never works that fast.  So I mostly use real film and forget the
polaroids, unless I hafta.

I searched deep in the catacombs of my darkroom storage area, but never
found the metal plates Clive was talking about ...... I must have found a
better use for them.

TigerShark



-----Original Message-----
From: largeformat-admin@f32.net [mailto:largeformat-admin@f32.net]On
Behalf Of Hornford, Dave
Sent: Thursday, March 08, 2001 8:50 AM
To: largeformat@f32.net
Subject: RE: [LargeFormat] Polaroid in cold


Based on this experience taking some Polaroid on a short winter trip (say 3
or 4 days snowshoeing or skiing) with a temperature of -15 C (5 F) should be
ok - but I should put the packets inside my jacket to warm-up before
starting developing and develop inside my jacket.

My interest in Polaroid stems from an observation that both of my older
shutters get more variable in the cold and I was hoping the Polaroid would
help me know how variable - but the variable ISO and a variable shutter is a
challenge.

If I understand the ISO right.. if I shoot at ISO 100 at an ambient of 0 C
(32 F) and develop at 15 C (60 F) my ISO was really 60 when I shot the
picture?

Dave

-----Original Message-----
I never froze polaroids for a long time, but i know that a brief freeze
(unintentionally left in the freezing car for a few days) did not harm them
at all.

At time of processing, the temp should be as close to ideal as possible (70
deg C) ... and it takes time to heat up the chemical pod after it has been
stored cold.  Some photographers will carry several sleeves of polaroid
under their shirt to keep them warm and will put them back under the shirt
while developing.

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