Long Term Frozen Storage

[John Cook]

As our favorite sheet films slowly cease to be manufactured and companies ride off into the sunset, there is a lot of talk these days about hoarding a lifetime supply of something and freezing it.

As a professional, over the years I have routinely purchased light-sensitive materials by the case and popped them into a dedicated freezer. But I have never run personal tests nor seen scientific data on maximum life expectancy of frozen film and paper.

I did however purchase and freeze a thousand sheets of factory-fresh HP-5 Plus in 1990. Five years later while running standard exposure/development tests with this film I noticed its bd+f was much higher than that of new stock. So I discarded the fogged supply and have never attempted long-term storage since.

Now that so many materials are disappearing, my thoughts have returned to this question. I just found a Kodak web page (one of several) which discourages frozen storage beyond six months. While the film does not chemically age very quickly at this temperature, apparently cosmic rays (I’m not kidding) continue to act upon the frozen emulsion to increase grain size and base fog.

Kodak makes it sound like long-term hoarding and freezing of film is just a pipedream.

Any thoughts or personal experiences would be extremely useful.

Here is the Kodak document:

http://www.kodak.com/US/en/motion/support/h1/storageP.shtml#p

[David A. Goldfarb]

It depends on the film speed. In my experience, five or six years is probably a good limit for a 400 speed film, but I've used some films like Kodachrome 25 that were stored for 10 years, and were surprisingly good.

[Michael Kadillak]

After reading the Kodak bulletin you made reference to, I did not arrive at a similar adverse conclusion. I have pulled all types of film that I have had in long term frozen storage and for reference developed an unexposed sheet even after six years of storage and I cannot differentiate any measurable negative effects to base fog even under the densitometer. And that goes for all speeds of film as I got sucked into the last scare a number of years ago about 5x7 T Max 400 as it could only be bought with a special order and I thought it was all over. Four months later it was a stock item.

The re-organization of Ilford I hope will result in a bump in sales as I made a large order on Friday. I hope that all users of Ilford products will stay the course, stock up to demonstrate their support and remain optimistic. The company wants to spin it off and the last thing we and they need are for folks to just bail out as that will hurt the sequence of events that I feel is both very probable and possible.

My recommendation John would be to put a year or two in the freezer and you shoudl be just fine.

[Annie M.]

OK I have in my freezer at this very moment unopened boxes of Tri-X 4164-EMUL5531 1997 & 1993 TMAX400-EML661 1996, and Plus-x 1996 (roll film). My understanding is that this film was refrigerated for the first 10 then frozen thereafter. I do not have a densitometer but if someone can give me a basic protocol I can do some simple testing. I am also curious about others experiences with outdated film because I am definitely going to start hoarding and I am wondering about the maximum timelines.

[Andre Noble]

Here's what 100
year old Ilford FP4+ adversely stored might look like. Imagine how good
it would have been had it been stored frozen.



Michael K., I'm with you. I gave Ilford a nice little sales boost myself with
a purchase of 1500 sheets of their FP4+ 4x5 sheet film, of which B&H is
now currently out of stock of their 100 sheet boxes.





Also, consider film manufacturers gladly provide expiration dates on their film boxes. They're dependent on continual consumption.

[Diane Maher]

I have some 4x5 Kodak HIE that has an expiration date of 1977 and as far as I know, it was frozen for all of that time. I've shot a few sheets, but haven't tried any since I got a Jobo. I was having problems with my development of all 4x5 before that, but will try again with it sometime soon.

[John Cook]

Annie, the procedure to detect fog would be to normally develop an unexposed sheet of your old film along with a sheet from a new package. Then compare the two on a lightbox or against something like a window against an even north sky. Compare the densities.

Without a densitometer, you can use neutral density Kodak wratten gels (assuming they are still made). ND 0.1 is a third stop, ND 0.3 is a full stop. Lay additional gels on the new film until the total density of gels plus new film matches that of the old film. Sum of the gels equals the amount of fog. Given an even light source, your eye is capable of sufficient accuracy to duplicate a densitometer.

Sorry, I have no idea of how much fog is acceptable. S’pose that is a personal matter.

I suspect that if you want to stash some film, get the slowest speed you can find, and use it up in five or ten years max.

[David A. Goldfarb]

I would say the amount of fog that is acceptible depends on the Dmax of the film. Michael Smith and Paula Chamlee have been able to use their freezer full of Super-XX for so long because the curve goes on and on in a straight line before it shoulders, so a little extra base fog can just be printed through with no change in Dmax, and since they contact print exclusively, the extra grain that may come from the base fog isn't terribly important. The old Super-XX may not be able to attain the N+4 expansion that fresh Super-XX could, but how often does one need N+4?

If they'd stocked up on Royal-X, they'd probably have tossed it by now. I tried processing some from an unopened box from the late 1960s, and grain and fog were unacceptably high, being a higher speed film more prone to fog from cosmic rays.

Modern thin-emusion films with lower Dmax and less expandability/pushability won't tolerate as much base fog before you run out of space at the top of the curve, and stocking up may not be such a good strategy for smaller formats, where the grain will be more of an issue.

[Annie M.]

John, I did as you suggested and the results were surprisingly good.... (consider the source though, I probably have the widest personal parameters of acceptability of anyone on the forum). By eye it is much less than ½ a zone increase in density (comparing to a grey scale neg).

Personally I will be laying down a 5 year supply of favourite vulnerable films and 10 years of anything that is discontinued.... gives the manufactures a boost in sales plus insures my supply. Thanks for your help.

Cheers, Annie

[ronald moravec]

Low speed emulsions have a two year life and high speed a one year life from the factory per Kodak`s help line. Cosmic radiation causes fogging frozen or not and higher speed stuff is more sensitive to it. Unless you own a lead mine, there is no way to avoid it.