The effects of delaying development of exposed film

[Paul Metcalf]

When a photon (light) or two make love (what else do you call it?) to a silver halide cyrstal in the film it absorbs the photons' energy and causes an electron on the halide crystal to escape out into the emulsion. If the electron runs into a positive trap, it becomes, well, trapped. If a free silver ion is near the trapped electron it may absorb the electron and be reduced to silver metal. If enough silver atoms are reduced (some think 4 is the minimum) as a "clump," then a latent image is formed. Actual visible image does not form until chemical development. So, the whole love affair takes light (photons). If exposed film is kept in absolute darkness, then I suspect that any degradation in the latent image is due to the general aging of the materials in the emulsion and should be no more than non-exposed materials. The warnings on the high speed film might be hand-wringing about the effects of beta and/or gamma rays from space, but isn't really an issue with normal speed film. The main reason to develop film ASAP is to make sure you aren't making any mistakes in exposure, etc. and/or your camera equipment isn't failing.

[tim atherton]

"He did cite one other fact which I left out of my (above) post, which was regarding Tmax P3200. He said that if an exposed roll is left for a year (presumably not refrigerated) without development, the roll is not worth developing and printing."

As I recall that's pretty much so for unprocessed TMax 3200 too - there isn't much point in storing TMax 3200 for very long in the fridge or out because it fogs so easily from cosmic radiation or whatever it is....

[Mark Sampson]

Perhaps the best reason to process your film soon after exposure is because you want to see your pictures.