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Protecting Unexposed Film from Cosmic Radiation?
iblink asks: "Last year Fujifilm stopped producing a color slide E-6 sheet film called Velvia 50. It has unique color characteristics that I love so I decided to purchase the remaining stocks in Europe. I now have hundreds of boxes that need to be stored for up to thirty years. A number of film experts assured me that freezing the Velvia would stabilize the dyes for long term use. However, they all mentioned that cosmic radiation would eventually fog the film, and they offered little help in finding a relatively inexpensive barrier. I found various ideas on proton cosmic radiation barriers — a big bucket of water, lead, certain plastics — but nothing convincing or sufficiently detailed (which plastic? How thick?). The film is currently in a freezer, unprotected. Any ideas?"
You do that and you'll probably end up with just as much radiation from Radon, uranium, etc.
SJW: Someone who has run out of real oppression, and has to fake it.
I think that I should warn you that everything eventually decays. Nothing lasts forever. And film, just like fruit, is best served fresh. If you really want to continue using Velvia in, say 600 years, I would recommend that you try to come up with some way of getting it fresh in the future. Just because Fuji stopped producing it, shouldn't mean that they won't be able to produce a small batch of it (at ridiculous high prices) if you make a special order. A different option, is to simply ask for the "recipe" (possibly by signing an NDA or similar contract), and get an independent laboratory to produce it when you need it. The last (and the only sane) option, is to try to find something else that fits your need. Such as analysing sample pictures, and coming up with a photoshop color filter that does the same thing.
If they bring it back with "substitute raw materials and new manufacturing technologies ," it won't be the same thing. Emulsions and our attachments to them are delicate things. Any change, however subtle, will kill the effect. The new film may be just fine. It may be sort of like the old film. But it won't be the same.
Think "New Coke." It was supposed to be the same, wasn't it? In fact, some bottlers changed formulas and put New Coke in remaining stocks of old cans. The first time I tried one of those, I literally did a spit take. It might have been a perfectly fine soda, but it was different. It wasn't what I expected and I could tell that a change had been made.
The human senses are far more sensitive than people realize. New Coke didn't fool me. A change in materials in a film emulsion won't fool they eye of a photographer who loved the old formula.
Now I'm going to go do some research to help this guy. He really does need to arrange good long term storage for his film.
If you are concerned about being able to use Velvia film in the long term, it might be easier and cheaper to get together with other like-minded folk and find a cheap contracting manufacturer somewhere like China or India who can copy the Velvia manufacturing process (if they bother follow licensing protocols...) to provide a supply of fresh film.
So you not only need protection against cosmic radiation, but also against terrestrial radiation. You could use a ventilation system to minimise the radon problem, but this will cost you a lot of money if you want to store the film for 30 years.
Also make sure your construction material isn't too radioactive; materials like wood, cement, stones, iron etc. all have a (low) level of natural radioactivity; stones from different sources have different natural radioactivity levels. Even very low levels won't do any good to films stored for 30 years. Bring a Geiger counter with you when selecting your construction material.
The cosmic radiation in question has enough energy to travel across the galaxy, blast through several kilometres of atmosphere, penetrate your building's roof and walls and then punch through the box holding your film before actually interacting with the film. Seems unlikely that you'll be able to do much more to keep the film fresh.
Did you also happen to buy and store a 30-years-worth supply of chemicals (and a processing machine) for E-6?
this just came to my mind:
you can try to protect with some kind of magnetic shield, to maybe trap these evil particles in some kind of "magnetic swirl" or like that....
hummm, but fast spining particles will radiate any way....
and probably you will need a lot of power (i mean $$$$) to produce a strong enought "force field"
well, just a few ideas.
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"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
That's a waste of time and money - because the material can have an activity level an order of magnitude below the counters detection threshold, and still have enough activity to be threatening to the film on the timescale of years. It's the accumulated (chronic) damage that matters here, not the acute damage.