How long can wait to develop (this) exposed film

I have 20 sheets of exposed but not developed 4x5 Tri-X 320 film. I have two questions:

1. How long can I wait until I really HAVE to develop these particular Tri-X sheets, so that I don’t have any degradation in image quality?
2. What is a good average timespan until I really should develop
a) black and white negative film
b) color negative film
before I may get degradation of image quality?

Days are fine. Weeks? Likely fine. Months? You run the risk of latent image degradation. (Ilford Pan-F Plus is particularly prone to this and you should stick to days, not weeks or months, if you use this film.)

If you can't process right away (within a couple of weeks), put the film in a sealed freezer bag and freeze it. Thaw it a couple of hours or so before processing.

Most films have very good latent image keeping qualities... except, apparently, for Ilford's Pan 50. I developed a few 8x10 sheets of TMY-2, and HP5 a few weeks ago, that had been sitting in a box, in a cupboard in my darkroom since 2008. Films that were shot initially as backups, and I was just too busy... or lazy... to develop. They turned out great. Good storage is important.
Normally, I like to develop film as soon as I can. Difficult if on a road trip, or on the other side of the globe, and can't get home for about a month... where I'm more concerned with aiport x-ray damage!

I've just developed some rolls of TriX 400 exposed some five years ago expecting the worst. They came out fine as far as i have printed already. Of cause I cant't tell if they had been better if I had developed them earlier

Ulrich

I've recently been processing Fomapan I exposed as long ago as 2007, with excellent results. Unexposed film that's been unsealed (120 in a 120 film can, but out of its wrapper, for instance) can be affected by humidity-induced mottling (apparently local loss of sensitizers due to condensation), but this doesn't seem to affect the latent images as long as the film was in good condition when it was exposed.

Now, how Tri-X 320 handles this, I can't say specifically -- but I've processed other films with latent images up to fifty years old, and if the age fog hadn't overwhelmed the latent image, they were generally very printable/scannable (though over that time span usually not "looks like I just shot it.")

Important Note: Once exposed, process PAN F Plus as soon as practical – we recommend within 3 months. This is the Ilford statement on page 1 of its leaflet about Pan F so it looks to be more than a matter of days

pentaxuser

Friend of mine took some photos, forgot about them, stored them, lost them, rediscovered them, and developed them fairly recently. Shooting log says they were shot in Sept. 2002 on Tri-X Pan 400. There is definitely some damage, but far less than you'd expect. They'd been sitting in the holders for nearly 18 years, albeit in climate-controlled storage (a closet).

pentaxuser said:

Important Note: Once exposed, process PAN F Plus as soon as practical – we recommend within 3 months. This is the Ilford statement on page 1 of its leaflet about Pan F so it looks to be more than a matter of days

Click to expand...

Sooner is better, regardless. Three months would be an absolute maximum.

Sadly, I have been bitten by the problem and have learned quite a lot about it. I have a bunch of 2006-expired 35mm Pan-F Plus that I've been using up since I acquired it in early 2007. I've kept it frozen at about -18 C so when used properly, the results have been excellent despite the age.

I got out of darkroom work for awhile and unknowingly forgot exposed two rolls of Pan-F Plus, one in the darkroom and one in my freezer. The one that was frozen turned out well, with no obvious loss of shadow detail. The one that was left at room temperature essentially disappeared! No edge markings. Really faint traces of image density on a few of the frames, but most were simply invisible. I know the processing was okay because it was the bottom roll in the tank of seven I processed simultaneously (which all turned out fine; some shot only week before last) and the leader was black, as expected. I expected loss of image density, but did not expect to lose the edge markings.

I think you can probably keep exposed Pan-F Plus for a long time - if you freeze it. I would need to conduct some experiments to see if there might be some loss of image density, but it would take a few years to know the answer. While I will try to avoid delaying in the future, for my purposes, frozen exposed Pan-F Plus is stable enough for me if I can't get to the darkroom for a few months for some reason.