In 1974, I took two pictures of my wife on a camping trip. They were extemporaneous shots, catching her off-guard, and in rare poses. Just after I took them, I looked down and saw that somehow the aperture setting had been knocked off its designated place, grossly over-exposing the two shots. I knew from the beginning that the margin of error on Kodak slide film was narrow. The lab that developed the roll confirmed my fears: There was no way to obtain a suitable print, much less an enlargement.
So I waited--42 years--and recently attended a digital photography seminar at the University of Houston, where they suggested trying digital scanning for similar situations. I rounded up a bunch of slides, including those two, and sent them off to digmypics. Service was first rate, and they managed to restore both pictures to an enlargeable state. Money well spent!!