High ISO film storage times

[giverin]

<p>I'm looking to stock up on some Neopan 1600 while I can still get it. I really like the film and will miss it when it runs out but I only use it infrequently.... perhaps five rolls per year.</p>

<p>I know that higher ISO films don't store so well past their expiry dates compared with some of the 100/400 ISO films and that fogging can be an issue. I'm trying to work out how many rolls to buy and its not a cheap film here in the UK so I don't want to overdo it.</p>

<p>If for example the film had an expiry date of Jan 2013 and it was kept in the freezer after purchase, how long after the expiry date would the film still give good results?</p>

[john_shriver]

<p>The freezer will slow down the rate of chemical degradation to a near stop. But the problem is that it won't stop the fogging caused by cosmic rays. You need a salt mine to deal with that, even a foot of lead will only put a slight dent in the cosmic rays. (Plus, a foot of lead around your freezer would probably cause the floor to collapse.)<br>

Kodak's Portra 800 is about the only high-speed film where they have managed to desensitize it to cosmic rays.</p>

[pc_b]

<p>Depends quite a bit on how high you live (above 5000 feet?) and how high natural radiation levels are around your place (geology). Very roughly: 5 years beyond expiration date when not going beyond the box ISO.<br>

Don't sue me, please, in case your films developed in 2018 will turn out overly foggy!</p>

 

[profhlynnjones]

<p>Any film manufacturer will tell you that freezing at or below minus 10 degrees F will arrest the aging process, and that includes frozen color film that have used successfully for 10 years out of date.<br>

Lynn</p>

[giverin]

<p>Thanks to everyone who replied.</p>