It is routine to put X-Ray film at -80C to make it MORE sensitive to radiation (and thus fog).
This has been known since the 1950s.
Also no amout of lead will save your film from cosmic rays.
I suggest you store it a -20 to lessen chemical degredation. You should get 5 years past the date for 400 speed, 10 years for 100 speed and maybe 25 years for 25 speed.
I suggest unless the film you have is no longer made and can not be replaced just buy more small batches.
Last edited by brianmquinn; 09-16-2012 at 10:48 AM. Click to view previous post history.