Doing that meant passing a good quality medium (8mm and super 8 films) into an awful but easy to play one (VHS).
This was made with an artisanal system that involved shooting the picture on the wall lighted by the 8mm projector with a camera, with huge losses of quality:
- frame deformation
- reduced definition
- color distortion
Technology today has improved a lot, but some unprofessional lab still use the shoot the wall with your camera system.
The only reason why people wanted to transform their films into VHS cassettes was the ease with which they could then watch them.
I know most of young people never used a video recorder in their life, and much less a super 8 projector, but believe me playing a videotape was far more simple than:
- taking the projector from the closet
- lay out a white screen
- load the film into the projector
- watching the footage with a loud playback noise
- buying a new expensive lamp every 10 hours of playing
So people used to agree to degrade the quality of their home movies in exchange for the convenience with which VCRs allowed the playback. The problem with that kind of transfer was that they turned an analogue medium into another analogue medium, and tapes perish much faster than films, so those who opted for that solution in the 90s today find themselves with VHS tapes that are barely playable.
But nothing is lost for those who kept the original 8mm and super 8 reels.