> I have two F100's (just got back into Nikon gear) and have no lockup problems. I >consistantly change lenses without turning the camera off - I just can't seem to >remember- and it doesn't cause any problems. I did experience early rewind once for >no apparent reason and also got an error message that required me to take the film >out and reload it: this happened after I dropped the camera from about 6 feet up and >had it bounce off a woden porch and land in a snowbank. (this was the first day I >used the camera). The camera has worked fine since this time. I guess they are built >fairly sturdily. Don