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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?"
I prefer using a fantastic group of four astronauts to block cosmic radiation. It seems to work well.
Vincent J. Murphy
Spandex Justice
Were any of the film experts from FujiFilm? They may have some guidance for you. As them how they store film stocks.
--Mike
You could use a very deep cave or mine, however this then presents other radioactive issues.
I note that it's now past late spring 2007.
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.
A Faraday cage won't stop particle radiation, nor will it protect against short wavelength radiation like gamma rays (unless you build a Faraday cage from massive lead plates, without any holes in it).
It also won't protect you against radioactive radon gas seeping out off the ground.
Forget about Velvia 50 & just move onto Velvia 100F like the rest of us have. 50 has little to no (most people would say the latter) advantage over 100f.
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.
Cosmic Radiation is very very very very short wavelength.... light for example is just nanometers order. Cosmic radiation is even shorter. Gamma Rays are as far (or close, it depends which side you are ;-) as 10e-16 meters (pico meters or less).
a tion#Electromagnetic_spectrum
http://en.wikipedia.org/wiki/Electromagnetic_radi
Obviously, there's a problem, know-nothing slashdot smartmouths be damned. Here's what Kodak says:
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.
I've heard that if you stack a bunch of red Fiestaware dinner plates, and then store your film sandwiched in layers between them, then cosmic radiation won't be an issue at all.
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.
Like lots of photo buffs, the first thing I thought of was the Rochester Institute. And that led me to an answer.
I'm not going to put directly on Slashdot the name and phone number of a real person. However, if you visit the Image Permanence Institute web site and poke around, you'll find a name and phone number you can call to get in touch with an expert on these subjects who will either know the answer or know where to find it.
You may want to investigate "Graded-Z shielding". The name comes from the fact that it uses layers of shielding with decreasing atomic numbers. You might first have a layer of lead, then a layer of tin, then one of copper. The lead stops the cosmic rays (protons, electrons, light atomic nuclei), but generates X-rays in the process. These X-rays might also fog your film. The X-rays produced as the lead absorbs the cosmic rays have a characteristic energy (88keV) which is not well absorbed by the lead itself - that's where the tin comes in. Again, the tin stopping the X-rays from the lead generates X-rays with a lower characteristic energy (29keV, which is in medical X-ray energy territory), which it doesn't absorb too well. The copper absorbs the X-rays from the tin and again emits X-rays with a yet lower characteristic energy. I don't know if the 9keV X-rays produced by the copper are a problem for Velvia. If they are, you'll need a yet lighter layer; a glance at the periodic table shows aluminium is a likely candidate.
I have no idea about the sensitivity of Velvia to cosmic rays or X-rays, so can't suggest thickness of the materials. My wild-ass-guess is somewhere in the 10s of mm. 30 years is a hell of a long time though. There are companies which specialise in shielding of this type (search for 'radiation shielding', 'graded-z shielding' and the like), they may be able to provide advice and sell you enclosures.
Chernobyl 'not a wildlife haven' - BBC News
Q: My film is being destroyed by cosmic death rays, what can I do about it?
A: Digital camera, Raid 5, good backups.
Q: But only velvet#50 has the unique qualities I'm looking for. I can't reproduce that with digital.
A: Photoshop CS7, Filters -> Artistic -> Velvitize.
Q: But I have to have REAL velvet#50 for all these Elvis and Bengal tiger prints I'm doing. I can't print on velvet with an inkjet!
A: I heard fujifilm has a good film that does this, see if they still make it.
Do not meddle in the affairs of sysadmins, for they are subtle, and quick to anger.
About 20 years ago I had a small surplus stock of Kodak E6 professional transparency film left over at the end of a project. The storage recommendations from Kodak were to store E6 cold and dry, so I bagged and sealed the films and put them in low-humidity cold storage. As an experiment I left the films there. The films developed ok at 8 years age with excellent quality, and again at 15 years age, but by then slight fogging was visible. Maybe the fogging was due to cosmic rays, or perhaps the photochemicals had degraded. Anyway, the experiment ended when the E6 processing lab I used to use closed down (soon followed by its rival firms). I kinda miss E6. Really excellent true color reproduction and high resolving power (IIRC, over 100lines/mm).
Note that he's talking about sheet film, not 35mm. He's presumably using 4x5" sheets with a field or view camera which generally don't have any electronics in them.
We're talking about something like this or this.
It's counterintuitive, but shielding can actually make more radiation. The problem is that when a high energy cosmic ray strikes a nucleus, it can make a whole bunch of secondary particles which still have a lot of energy. Then those particles interact again, and so on, producing a "shower" of particles that can interact with your film. Sensitive neutrino experiments go far under the earth's surface to avoid cosmic rays, and even there they get a fair number of (low interacting) muons. I helped test a large space astronomy observatory and we regularly got blatted by cosmic ray showers, even though the observatory was inside a pressure vessel with thick steel walls. Proper shielding is an art.
Burying your film underground may make things worse too... if you live in an area rich in radioactive soil or radon gas. Building materials like concrete can often also be contaminated with uranium.