Re: [Avid-L2] 29.97 and HD / RANT

This is getting fun, and deep. Time for the engineers, which I am not, so feel free to elaborate and correct. I'm totally open to learning. Yes, ATSC technically allows all those rates. In pure digital video you can have any frame rate you like, even variable frame rates. Gamers talk about their "frame rates" all the time. 

Can anyone name an outlet that specifies 24.0 other than cinema? 

Does anyone know of any outlet that specifies 30.0 rather than 29.97?

Analog video devices have a sync rate specified in hertz. Modern monitors can sync to a wide range of frequencies, but this ability exists because of computers, not television. "Televisions" run at 59.94hz (in America), because that's what they've always done. I'm currently setting aside the bullshit "120hz" phenom because I don't honestly know what the frequency actually is there. The reason 23.976fps and 29.97fps exist is to synchronize with this standard frequency. Hence, my reference to 23.976 and 29.97 as frequencies, but I stand corrected. Frame rate and frequency are, indeed, not the same thing. Most monitors cannot even run at 23.976hz. It's too slow. They run at a multiple of 23.976 when displaying a 24fps signal (Blu-ray and DVD), or they add pull-down and run at 59.94hz.

In theory, ATSC allows other frame rates, but does anyone actually use them for delivery?

Cheers,

                 tod

On Aug 3, 2020, at 10:02 PM, Mark Spano <cutandcover@gmail.com> wrote:

Please don't spread this. It's false. It might have been true at some point long before the HD days, but I guarantee you can have all of the following frame rates in video without blinking.

23.976

24.0

25.0

29.97

30.0

59.94

60.0

And many more!