TV wasn't developed to show film but to show live action captured by a video camera. They needed a way to have both the TV camera and all TV sets to operate at the same frame rate. The TV scan rate is derived from the power line frequency (60 Hz in the US, 50 Hz in the UK) which is very stable. There was no easy way to sync a TV scan with the broadcast if the frequency was some odd number like 20 to 24 frames/sec.

Last Edited By: PJAceto Feb 2 12 6:07 AM. Edited 1 times.