Re: The C.A.S. and Digidesign Present
hi don,
when video was developed in the 1920's, the first TV's used phosphers. these were not fast enough to handle 30 FULL frames per second, so the engineers decided to tie the 60 FILEDS per sec to the AC cycles. but this was for B&W. when color television was being developed, engineers looked into how to make the new NTSC system backwards compatible with the old monochrome system. they thought by adding the color information on a sub-carrier, they could transmit both sugnals and still use the old radio transmitting technology. but this color signal would interfere with the audio subcarrier. so, it was decided to solve this by fractionally adjusting the frame rate of NTSC television from precisely 30 frames per second (60 interlaced fields per second) to approximately 29.97 frames per second (approximately 59.94 interlaced fields per second).
just another example of an engineering solution that makes things practically very over-complicated.
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