Well I'm sure it's happened to all of us, I have some old negs with creases in them and my scanner objects.........I suppose heat has to be involved somehow, but before I try my bodges thought someone might have found a good/easy way, although I'm not expecting "as new" results.
I tried once with so so results by soaking the neg in 68F water for about an hour. I then flattened it between, as mentioned above, between two pieces of glass for another hour, resoaked and then rinsed in photoflo and let dry. It is printable I suppose. Just how so, not sure. I ought to find out, huh?
Once upon a time I let one sit between the pages of a very heavy stack of books for a couple of weeks then printed with a glass negative carrier and it worked out fine.
If its in a strip - 35mm or 120 - rewashing then hanging it to dry with weight on the bottom might help flatten it enough to print in a glass carrier. All depends on how sharply its creased.
Yeah. Heat can do bad things to film. Whatever you do I wouldn't stray too far from processing steps to correct it. You know anything there won' hurt the film.
Well it seems there is no quick sure way solution, anyway I had no idea how to apply continous heat (something like 40-50c) to the neg whether between glass or a weight on the end, or if it would work.....and it would seem ridiculous in cost for any length of time, I'll just leave the negs sandwich in a heavy book for a year or two and see what happens...thanks.
There's no way to fix it. The only solution is to fix the print. In the olden days you'd do it with an airbrush and paint brush and masking. Nowadays you can fix the scanned negative in about 5 seconds by pressing J in photoshop and going to work with the spot healing selection tool. No joke about the 5 seconds part.