How safe is freezing film and enlarger paper?

[Rob Gertler]

I have several questions about long-term frozen storage of B&W film and B&W enlarger paper: 1- Is there an upper limit regarding how long film and paper can be stored? 2- Is there any deterioration with time in frozen storage? If so, what happens? 3- Is there any difference with storage properties of sheet 4x5 and 120 roll film? 4- Are there any special instructions and precautions for storage in a freezer? 5- Can previously opened containers of film and paper be safely stored in a freezer? Any special precautions for doing so? Thanks in advance for your help.

[Philippe Gauthier]

My answers are valid for film only; I don't know the answers for paper.

1. No, not really; but see 2.

2. Yes. Cosmic rays, that strong enough to go through the Earth, go through your film and slowly fog it, as any type of radiation. This fogging process is slow, but its speed is in direct relation to ISO speed. Significant damage, which takes the form of an increased base + fog level, will take decades with ISO 100 film, a few years with ISO 3200.

3. Not that I know of.

4. Store your film is a sealed container, to avoid excessive drying or moisture growth.

5. It's better not to, but it can be done. The issue here is the build up of humidity/frost on the film. Open the container as little as possible and if you do, use silicate gel to avoid moisture/frost build up.

[Michael Kadillak]

Clearly storing film and paper in a freezer is a good thing, otherwise folks would not have been doing it for years. As Phillip said, sealing it from moisture is recommended for both. Michael Smith has had Super XX film in his freezer for about 15 years and aside from an inconesequencial amount of increased film fog that he can compensate for in his development, it is a non-issue. With paper I feel it is more of an issue and is dependent upon the type you are using. I have had conventional silver papers go to hell in a handbasket with fog but I hear that Azo from the 1930's even without being in a freezer is perfectly usable. My advice is to use your conventional elnarging papers as quickly as you can just to be safe and don't worry about your film. If you feel a need to store a quantity of film in your freezer, seal it in a bag and don't worry about it as it will be just fine.

Cheers!

[Jim_3565]

I'm not sure Michael would say that the fog he and Paula experienced in their Super XX stash is inconsequential. Maybe he'll weigh in on this issue.

I do know that they got significantly greater fog by storing film in a stainless steel freezer with insulation (i.e. dielectric) in between the steel sheeting which formed the walls of the freezer. Two metal plates with a dielectric sandwiched in between them form a capacitor, which stores energy from the cosmic rays. In parallel with the resistivity of the metal (which provides resistance), this arrangement is an RC network which emits an infinitessimally small, albeit significant, electric field as it dribbles current. In other words, a cosmic ray amplifier. The effects are cumulative over time.

As I understand it, Michael and Paula now store their film in a concrete block freezer.

[Steve Baggett]

It won't matter matter what material the "freezer" is made of, with regard to minimizing the terrestrial-source background radiation. About 8% of all background radition is "cosmic" in origin and about 8% is "terrestrial" in origin, i.e from the materials all of our "stuff" is made of such as metals, stone, plastics, wood, etc. Any sample of concrete (or any other material) will always contain trace amounts of uranium and its decay products, including thorium, radium, and radon. The sources for the 300-400 millirems/year of natural background radiation that all of us receive (including our film) are ubiquitous and inescapable. It will be higher at some geographic positions on the planet due to local geology but will never be zero on earth, anywhere. Link

[Michael A.Smith]

The materials out of which a freezer is made will make a difference Alternating layers of inorganic (metal) and organic material (insulation) concentrate the energy. Block walls do not.

[Ole Tjugen]

Michael, the material doesn't matter as long as we're talking cosmic radiation - or background radiation, for that matter. As long as you're not building a freezer out of 5" thick lead, at least...

Metal or not will only matter if the radiation is in the shortwave to microwave range, which cosmic radiation typically isn't. Nor is normal film sensitive to it. If you want to block all electromagnetic radiation, you can build a faraday cage - or remember to close the lid on a metal freezer.

Concrete will have far higher natural radioactivity than sheet metal, so should not be used if film longevity is that critical.

[Jim_3565]

The metal freezer might also have had current flow due to a short circuit or induction from the B field created by the compressor motor. The point is: the film fogged.

[Michael A.Smith]

I'm not writing about what is usually called "cosmic radiation." Nor about radiation from radioactive materials. And it is not electromagnetic radiation either. The radiation I referred to has been called "Cosmic Life Energy," It is very real: detectable and measurable. This is not the place for a discussion about it, but involves science I have been involved with and worked in for forty years. Unconventional science to be sure, but that does not make it any less valid. New science has never been immediately accepted by the powers that be in the scientific at the time of the major discoveries.

[Richard Fenner]

Oh boy. NOW it starts to get fun.