"That was the worst part, getting the roll back and realizing the exposure was wrong for the entire roll, or some other setting was off."

Totally off-topic, but this reminded me of a time when I set my little minidisc to record a whole four-hour session in the pub. I couldn't fit a whole four hours'-worth on, so I set the recorder going at the start and pressed pause at the end of each bit of music, cutting out all the chit-chat. Only thing was that, consistently for the whole four hours, I'd paused all the music and recorded all the chit-chat...not a single note of music. Some very incriminating blokish stuff on there...I did the honourable thing, threatened blackmail then deleted it all...