Yup - I (and lots of other people : ) have considered that option, but equipment isn't readily available, so it's a bit of DIY needed there, and when working with old, brittle film, this adds to the risk. I suspect the process would be very time-consuming, and generate huge amounts of data.

An easier / cheaper way that seems fairly popular is to buy an old projector, set it up square to a good screen / wall in a very dark room, and just record that. The quality loss is probably going to be modest, given the low-quality of the original material in any case.