I first built my Super 8 telecine adapting a projector, then built one with a self made simpler film transport system and now I’ve just finished building a film scanner to handle my Super 8 and 16mm films and still negatives and slides. I have spent many hours looking for options for the back light, capture cameras and have explored various ways to advance the film.
Firstly, in my experience a CCD sensor with a global shutter is better than CMOS, machine vision cameras are better but can be pricey. I have looked at all sorts of consumer digital cameras and they all present various issues, they’re too slow, it’s difficult getting decent optics with manual controls on them and unlike machine vision cameras most aren’t always able to be controlled via the computer. Personally I feel that projectors are not ideal to transport film at slower speeds, they are rough and need constant tweaking and fiddling about with which is why I created my own simple film transport.