How long can ISO 25-400 B&W films be kept?

[bwfans]

For common B&W films, ISO 400 or under, how long can they be kept in a dry cold place, like a freezer, and still reasonably good to use? What is the best record?

(actually I have this question for color or slide film too).

My question is caused by following interesting post and picture:

(there was a url link here which no longer exists)

 

[bobfowler]

How about one heck of a long time...

I only wish I had more of it (VPS-III), when these boxes are gone, so ends my stash!

 

[jandc]

For common B&W films, ISO 400 or under, how long can they be kept in a dry cold place, like a freezer, and still reasonably good to use? What is the best record?

(actually I have this question for color or slide film too).

My question is caused by following interesting post and picture:

(there was a url link here which no longer exists)

ISO 25-50 Speed B&W films last a very long time. They are so slow that backround radiation is not a major factor in their decay. In adition the chemistry of these slow emulsions is very stable. There was a time that Efke didn't even put expiration dates on their PL25 sheet film. 10 years is nothing to these films. I have Panatomic X from the late 70's that is still nice.

ISO 400 and higher films are the exact opposite. They are sensitive to backround radiation and their chemistry is not as stable as slower films. Even frozen, which retards the chemical decay but not the radiation component you can see increased base fog past expiration. When this base fog becomes an issue is debatable. As Michael Smith has shown significant base fog can be dealt with and very old film used successfully.

The 100-200 speed films fall in between.

I recall reading that Sandy King had tested the base fog of Michaels film. Knowing the base fog and how old his film is would give you a feel for what to expect.

Finally there is a significant difference between a cool place like 50-60 degrees and a freezer. We have seen base fog double from what we measured in new stock just a year after expiration at cool room temperature.

 

[Mark Layne]

I have EFKE 100 and R17 that are 30 and 20 years old in the freezer and Panatomic X that sat in a bulkloader unfrozen for 15 years. They are all fine

 

[gma]

I recently developed some 4x5 Agfa APX 100 that expired 7-92 stored in my closet. It was fine with no fogging. I have 25 sheets of Kodak Ektapan (100) that has been frozen since it expired in 1975! I have a new box of Ektapan frozen also. I plan to expose and process sheets from each box and compare.

 

[Konical]

Good Evening,

Just a couple of years ago, I used some Kodak Commercial Copy Film 4127 which was dated early 1980's. The film is rated at 50 (daylight) and 8 (tungsten). The sheets I used had not been frozen, not even refrigerated at any time. Even so, there was just the slightest hint of deterioration (minor apparent fogging) along one side of the image; even that effect may have been caused be a little light somehow leaking into the top edge of the foil package at some point. Right now, I have several hundred sheets of the stuff frozen and expect that it will be just fine several decades hence.

Konical