Re: [APML] Speeding up film with cold weather

[Alan Voetsch <critter12952@yahoo.com>]

--- Mark Bohrer <lurchl@ix.netcom.com> wrote:
> Cold temps may buy you less dark noise with
> CCD-based cameras, but that's it.

Hi Mark,

I'll quote from the book by Jack Newton and Terance
Dickinson, page 108. 

"For every drop of 20 Celsius degrees (35 Fahrenheit
degrees) most films gain about one f-stop; that is, a
400 speed film acts like 800 speed film around 0
degrees C (32 degrees F) and like 1600 speed film at
minus 20 degrees (-4F), and the process keeps going.
At minus 40 degrees (-40F), a 400 speed film is
running at about 3200 speed. Once again, these are
rough guidelines, and they vary from one film to
another, but when the temperature gets close to
freezing or below, all films show this increase in
speed to some degree."

For whatever reason, they seem to feel that this is a
real effect. All I know is that if I can get in a
couple of hours what has been taking me 4-5 hours to
get, I think I'm going to look into it.

Alan

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