It was an SQAi with a 220 back on it. Problem was the shutter seems like it didn't fire when it should have. I went through the motions, advanced the film and shot the next. The frames are perfectly clear where it missed and perfectly exposed where it worked. I've never seen it do that before. All the shooting was in the space of 30 minutes just walking around the cabin. Lenscap was never back on the lens and was never bumped or joggled to misfire it. Only other thing I can think of if the frame counter skipped a slot as I wound the film.