Originally Posted by wolfyncsu7
Ok... makes sense. And then supposedly if you take this signal and display it at 48, 72, or some other multiple of 24 Hz, it will be less jerky?
The key is making sure that source frames of equal duration turn into display times of equal duration.
Displaying 24p content at 60i/pi means that half the film frames are displayed for 2/60th of a second, and the other half are displayed for 3/60th of a second. So, a smooth pan comes out with a jerky "judder." 60i/p doesn't matter at all for judder. What we want is to have each film frame to be displayed for the same amount of time. 24, 48, 72, etecetera doesn't matter for most display types (obviously refresh rate is a big factor for CRT).
If anyone gets a chance to check out our HD DVD truck tour, you'll see HD DVD being played out as 48 Hz through a great Marantz projector. No judder, and without the flicker of a 2-blade projection system. Very, very nice stuff.
Note that the distinction between "native" 24p and inverse telecined 24p is inconsequential as far as the final image goes, since 3:2 removal is an entirely reversible process (basically you insert 12 repeat fields on playback, and then take them out with image processing). Additionally, a properly made HD disc today should be fully compatible with 24p playback in 24p native players (like the aformentioned laptop players).
There's been speculation about whether or not "24p" is going to matter in the format war, but there isn't any practical barrier to doing good 24p with either format.