Frozen Film & Background Radiation

[DmaalaM]

I have read some discussions about frozen film keeping but only going bad because of background radiation. Would a lead container like the old Airport Lead X-ray protectors protect it from background radiation? Have any of you guys tried this?

 

[MattKing]

The background radiation comes from cosmic rays, and no bag is going to be able to stop them.
If you have a really deep, unused salt mine in your back yard, that would help.

 

[Tom1956]

Nope, the salt fumes will fix the film. Burying them 1000 miles under the surface of Pluto is your only hope. Better send the film to me. I have and anti-cosmic ray machine. And I guarenttee each roll because I test them in my Nikkormat before returning them.

 

[Gerald C Koch]

When I was in grad school we used 8 inches of lead to reduce the background radiation for our low level counter. Hardly practical for in home used.

BTW one of the principle sources of background radiation is from potassium K40 --> Ca40.

 

[Tom1956]

I wonder if there's a cosmic ray app. But I don't have a cell phone anyway. But I bet there really is an app for that.

 

[Oren Grad]

T-Max P3200 was especially susceptible to environmental radiation, so much so that refrigerating or freezing it wasn't much help in extending its useful life. But I don't know of any current film for which ambient radiation in typical home settings is a problem even for long-term storage.

 

[cliveh]

It's those neutrinos that really do the damage, they can play havoc with contrast ratios.

 

[snapguy]

bill gates and salt mines

When I was a cheeky young photographer I toiled for the world's largest news service, as a photog, for a while. Bill Gates owns the news service's library of fabulous photos (some, not mine, are Pullet Surprise winners) stored in an old salt mine and some of my efforts are down there. I don't know what he does with his unused rolls of film, presuming that he has any.

 

[NedL]

It's those neutrinos that really do the damage, they can play havoc with contrast ratios.

Aha, that explains why some of my photographs lack "punch" or look uninteresting. I knew there had to be a good reason.

I'm not sure much background radiation from radon or alpha particles like you can detect with a geiger counter could make it through the metal of your freezer or refrigerator. But cosmic rays can get through a lot. If you are interested in learning something really mind-bending, read about muons that are created in the upper atmosphere by high energy cosmic rays. They have a VERY short lifetime, not nearly long enough for them to make it down to the surface of the earth even at velocities approaching the speed of light. Yet they do reach the surface of the earth and the reason is special relativity... one way to describe it is that due to time dilation, from our frame of reference time is slowed down so much for muons that they exist long enough to reach the earth. Their short lifetime happens in their frame of reference. They only reach the surface of the earth because they travel at relativistic speeds. The rate is about 1 per cm^2 per minute, so your thumbnail is getting hit by one about once a minute... and each sq cm of your film in your freezer.... which makes me wonder if film would be more or less damaged if the spool was stored upright or on its side..... hmm

 

[Tom1956]

We learned about cosmic rays in junior high. Very interesting. There's nothing that can stop them all.

 

[brianmquinn]

See:
The Strange Case of the Cosmic Rays (1957)
http://www.youtube.com/watch?v=k_wt5AFjRQo

 

[Ronald Moravec]

6 feet of lead is required.

 

[dorff]

Cosmic rays are not rays but particles, for the most part. Gamma rays originate from several naturally radioactive compounds found on earth, but they are shielded to some extent by concrete and other dense materials. If you have the option, store only film in your fridge, as for practical purposes most gamma rays originate from potassium (K-40), and having food in your fridge brings more potassium in close proximity. That said, I doubt whether it is such a big deal for slow/normal speed films.

 

[pdeeh]

finally, an explanation for my poor compositions - the cosmic rays are jiggling all the Silver halide atoms over to one side a bit

 

[snowblind]

BTW one of the principle sources of background radiation is from potassium K40 --> Ca40.

There you have it -- don't store your film with your potatoes!

 

[DREW WILEY]

The faster the film speed, the more the issue. I still have a few rolls of long discontinued high-speed this or that in the freezer, but strictly as
momentos. I have no intention of shooting them, because they undoubtedly spoiled long ago. The salt mine is where I work. My darkroom is
where I escape the salt mine.

 

[Jaf-Photo]

Film photography is really not the right hobby for OCD:ers. Just imagine trying to compulsively block out cosmic radiation from your freezer...

 

[PKM-25]

In 2007 I bought 50 rolls of Aerographic 2424 which is basically HIE in 70mm, a guy named David Romano re-spooled it and sold it as ready to shoot 120. I did a test right away with it and compare rolls I shoot now and I see no increase in base fog which truly surprised me. I keep it well frozen and I live at 8,000 feet.