During the transition from film digital, there were "digital backs" for some specific models. That this 35mm roll form factor works with any camera is neat. A

During the transition from film digital, there were "digital backs" for some specific models. That this 35mm roll form factor works with any camera is neat. A different idea to keep in mind is that a lot of the value in a camera system is not from the body, but from the lenses. Nikon DSLRs will take old film-era Nikkor lenses, and there are also various adapters for using older lenses on modern DSLRs. There also at least used to be a cottage industry of modifying some old lenses that couldn't be used as well with adapters (such as if the adapter introduced too much distance between rear element and sensor, or if there was a protruding motor shaft).