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View Full Version : How safe is freezing film and enlarger paper?



Rob Gertler
4-Feb-2004, 11:09
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
4-Feb-2004, 11:18
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
4-Feb-2004, 11:28
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
4-Feb-2004, 14:24
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
4-Feb-2004, 18:23
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 (http://www.nrc.gov/what-we-do/radiation/sources.html)

Michael A.Smith
5-Feb-2004, 01:33
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
5-Feb-2004, 06:56
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
5-Feb-2004, 07:34
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
5-Feb-2004, 07:35
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
5-Feb-2004, 07:47
Oh boy. NOW it starts to get fun.

Kirk Keyes
5-Feb-2004, 11:49
Micheal - I'm interested in hearing more. Can you supply us with a link or other source for more information on this so-called "Cosmic Life Energy"? Also, could you describe the design of the concrete block freezer that Jim Shanesy claims you have built?

Micheal, you also state "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."

You may have been oversimplifying things for us, but I would like to point out to you that if your concrete block freezer uses an organic material for insulation inside of the concrete blocks, you also have a system of alternating layers of inorganic (concrete) and organic material (insulation) which would then concentrate the energy, and fog your film, at least according to your theory.

Jim, you state "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."

Jim, could you show where our photographic film and papers are sensitive to electrical fields? And I don't mean the high-voltage, high-frequency electricity such as that used in Kirklian photography (which really only photographes the glowin the air around the object caused by the electrical current, and not the electrical current itself). Do I need to aviod placing my film next to my timer, or the electrical wires in the walls? How much fogging am I getting from the motor in my Jobo?

I realize that this is a large format photography forum, but I really think that any claims (especially extra-ordinary claims) made here need to be supported by evidence. I have seen this 'cosmic ray amplification in freezers will fog film' claim made before elsewhere, but I find the claims to be unfounded. There is already enough "black-magic" in photography that I don't think we need to help propagate any more.

Kirk

Rob Gertler
5-Feb-2004, 13:21
Thanks for all the input. But, to get back to the issue of safety of freezing film, is there a significant degree of fogging or other deterioration, and how quickly does it happen? More specifically, if I buy a whole lot of Fuji Acros 100 film now, will it be significantly different in 5,10,15,20,25 yrs. I'm not planning on being around more that 25yrs, so that is the upper limit of what I'm interested in. Thanks again, I appreciate you help.

Conrad Hoffman
5-Feb-2004, 14:58
Film and paper deteriorate at a *very* slow rate when frozen. The chemical reactions slow down by the usual rules for such. I suspect manufacturers don't run emulsion batches as often as we think, but put the stuff in cold storage until they need it. 10-20+ years of storage should be no problem for normal speed materials.

As for unconventional science, one of the myths is that the normal science community rejects such stuff out of hand. The reality is that a large number of very skilled and knowledgable people would love to make their mark in the world, and they take a good hard look at just about every so-called crazy idea out there. Should any phenomena show up that can't be explained, it draws a large interest until it is. Scientists go after loose ends like a hungry dog after a pork chop. Unfortunately, many ideas that have proven to be dead ends seem to perpetuate themselves. Or, their perpetuators just can't accept or understand the true explanations. Many of the "free energy" folk haven't learned all they need to know about measurement, particularly bandwidth, phase, and strays. The "low frequency electric fields cause cancer" folk haven't proven their case in decades of studies, yet this crap still gets into the legal system in the form of safety standards. (notice I didn't mention HF fields, which can cause problems) Did Tesla really invent a "death ray" that no one including the military has been able to figure out since? Doubtful. Anyway, the burden of proof lies with he who makes the claim. Life energy and energy concentrators? Show me.

tim atherton
5-Feb-2004, 16:27
also see the notes on this thread about Wilhelms book

http://www.largeformatphotography.info/lfforum/topic/497654.html

Kirk Keyes
6-Feb-2004, 11:28
Rob "But, to get back to the issue of safety of freezing film..."

The two major things that need to be looked at to solve your question are how fast will the film fog from radiation and how fast will the chemical reactions proceed that can cause film to fog.

The environment you store the film will determine the amount of fogging from radiation - the film will be exposed to radiation from several factors, notably cosmic rays and background radiation from the earth. As Steve Baggett said above "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." Not much can be done here to slow down fogging except for shielding from the radiation, and that will only work against some of the sources of the radiation.

The other aspect that no one has mentioned is how quickly chemical reactions that can cause the film to fog proceed. That's the whole idea behind storing the film in a freezer. And by this I mean the breakdown of compounds (i.e. the chemicals used to manufacture the film) which could cause fogging, or perhaps a loss of the film's actinic properties. I really have no idea as to what chemical reactions we really need to worry about here, but I suspect things like the decomposition of dye-components in color films, or perhaps the silver halide reacting with compounds such as sulfur that naturally occur in the gelatin...

Anyway, to answer this, we need to look at what is called the Arrhenius Equation. As we all know from looking at our film processing temp/time tables, the higher the temperature, the faster a given chemical reaction will proceed - the Arrhenius Equations models this process.

The relationship between the rate a reaction proceeds and its temperature is determined by the Arrhenius Equation. In a nut shell, at higher temperatures, the probability that two molecules will collide (even in solids) is higher. This higher collision rate results in a higher kinetic energy, which has an effect on the activation energy of the reaction. The activation energy is the amount of energy required to ensure that a reaction happens.

The Arrhenius equation is: k=A*exp(-Ea/R*T) where k is the rate coefficient, A is a constant, Ea is the activation energy, R is the universal gas constant, and T is the temperature (in degrees Kelvin = Celcius+273).

Now that equation looks fairly simple (!), but the things that we don't know to solve our problem here are the constant A and the activation energy Ea.

So for a rough estimate, chemists often approximate the rate of a reaction by noting that many reactions tend to proceed twice as fast if the temperature increase by 10 degrees C. That also means that a reaction will proceed half as fast if we decrease the temperature by 10 degrees C. If you have a freezer that is set to 0 degrees F, that equals about -18C. The difference from room temperature (20C) is then about 40C. That means we have 40C /10C = 4. So our reaction should proceed 2^4 times slower - 2x2x2x2=16 times slower.

So, if this approximation holds for our films, then the rate of any chemical reactions that fog our films should slow down by about 16 times if stored in a freezer at 0C versus storage at room temperature at 20C. So one could conclude that if the manufacter says you have a 2 year expiration date on your film, you may be able to have it last about 32 years.

But remember, this is an off-the cuff internet approximation, and not the result of any actual research on the cold storage effects of photographic films. And it also does not take into account the fogging effect of radiation, which may severely shorten the cold storage life of your film.

I hope this has given you some ideas on the information you asked about. My question is would you really want to or can you really afford to buy enough film to last 30 years? What if you change your mind on the film you like or even the format you want to use? I still have several rolls of 120 film that I bought when I had a medium format camera, but I sold that camera about 8 years ago...

Kirk

Rob Gertler
6-Feb-2004, 16:39
Thanks to one and all. I certainly have learned alot of physics (and, I think, metaphysics) from your answers. Regarding the issue of wanting to buy alot of Fuji Acros 100 and keep it in frozen storage, my answer is probably yes, if it does not deteriorate. Fuji Acros 100 is, by far, the best 4x5 and 120 size B&W film that I've used (and I have tried more than I'm willing to admit to). Its virtues include: miniscule grain, very high accutance (especially when developed in FX-1), the same emulsion in both 120 and 4x5, very little reciprocity failure, and the 4x5 size is available in ready-loads (which, while expensive, completely ends problems of dust on the film). Now, to get back to the safety of freezing film, other than fogging, isthere any other deterioration with storage (cracking, reticulation, etc.)? Thanks for your teaching me.

John Kasaian
7-Feb-2004, 21:36
Rob,

I don't think you'd have any deterioration with aerial film, which is routinely used at high(freezing) elevations with no apperent ill effects(the camera lenses are heated, but the bays where the film magazine is located is, AFAIK, unheated and unpressurized(BTW, theres lots of radiation up there, too!) This is film on an Estar base. I don't know how this would equate to what you could expect from Fuji Acros under similar conditions, but Estar material has been around for years. I'd think Fuji would use an equivalent product as a base material. My meager stash of verichrome pan seems to be none the worse for it's "big chill." I don't know what base that stuff is on. -----Cheers!

Al W
10-Feb-2004, 08:45
Rob,

The most important thing to remember about freezing film is;

Keep it in a sealed container in the freezer, and take it out of the freezer several hours before use, so it can warm to room temperature. A large amount of moisture can be drawn into a packet of film if it is exposed to the air while the film is cold. Film with a temperature below the dew point will form dew.