I've had this issue on 2 films now, Ilford Delta 400 and 3200, both developed in Ilford DD-X. There's a vertical fogging which appears stronger at the start of the film roughly 2 frames apart, then reduces in distance towards the end of the film and becomes lighter. The pattern of the fogging would seem to suggest it was somehow fogged in the canister. It also looks like the fogging is showing the pattern of having gone through layers of the film. Both are in date. (It looks like this film is underexposed/underdeveloped, but my main concern is the fogging.)
I've double checked my Paterson developing tank, I've double checked my camera is light tight by loading, shooting a film and shining a very bright torch at the edges and film window where light leaks could happen, and haven't been able to recreate the effect. In my view this leaves an issue with the film itself or its storage. So far as I'm aware it hasn't been x rayed. Maybe it's possible heat has caused this?
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I've double checked my Paterson developing tank, I've double checked my camera is light tight by loading, shooting a film and shining a very bright torch at the edges and film window where light leaks could happen, and haven't been able to recreate the effect. In my view this leaves an issue with the film itself or its storage. So far as I'm aware it hasn't been x rayed. Maybe it's possible heat has caused this?
Dead Link Removed

