Document cameras like this work very nicely, but there is one small downside I've noticed: their framerate tends not to be very good. That's usually not a probl

Document cameras like this work very nicely, but there is one small downside I've noticed: their framerate tends not to be very good. That's usually not a problem at all, but I have a couple of physics demos where I roll things around on an overhead projector, and the document camera often can't keep up with quick motion. Simple analog light and shadows obviously have no issues with that at all.