Quote:
Originally posted by Glimmie
Something on ABC that was origionated in 720p/60. Or a transfer that was converted from 1080/24 to 720/60. I do know that "Spin City" is a 24p film transfer to 720p. Pure progressive all the way through.
The other way to see true 24p is 1080/24p into a DLP projector. The commercial units do not update static pixles. Meaning only the pixels that change are updated. Of course they are still being modulated to produce gray. This look svery much like film. To see this you would need to be in a digital cinema or timing theater.
In the production enviornment 24p is actually display nativly as 48fS. This is so that 24p is compatable with interlaced equipment. The image is captured in a progressive scan manner but every line is on a different field. Delays are used to make the two fields line up when put back into progressive. You can view this 48fS signal and it flickers much like 625/50. It is important to realize that 48fS is not the same as interlace since the image was captured in a progressive manner. |
And 48sf flickers like an SOB on a Sony broadcast monitor

. At a SMPTE meeting last fall, Sony did a 24p demo of their newest camera, but they didn't have any display that did 24p well so it turned into a 60i demo very quickly. 48sf was givng the crowd bad headaches.
I really wish they could shoot more stuff at 60sf this would provide slightly better motion, allow backwards compatibility with 60i TV sets. And yet present a signal that future progressive display could weave for 30p playback. In short a, good compromise.
But as Glimmie states, they are "shooting" for a world market and 24p is the easiest way to fulfill that market.
Todd H,
I agree completely. I don't think that motion looks very good at 24p either. Motion is naturally blurry unless the exposure time is set low which gives you the jumpy Saving Private Ryan effect. Altough I have only seen brief glimpses of ABC's 720p Monday Night Football many moons ago, it was spectacular in regards to motion (and 720p is still more resolution than 95+% of the HD displays can show)
Interestingly the Sony rep said car chases look similar at 24p and 60i when encoded at full bit rate ATSC. With the 24p you get blurring due to the long exposure time while 60i you get blurring due to the limitations of the MPEG encoding.
To satisfy a world audience it would be nice if program material could be shot at a variant of 120 frames per second with the exposure time being derived digitally. For the 60p crowd, average two frames together. For the 24p crowd average 5 frames together. Somthing like that. Of coarse the data rate would be massive and beyond today's hardware. But it is still fun to dream.
-Mr. Wigggles