OK, does anyone know if it is possible to mix 60i and 24p 2:3 telecined to 60i on a DVD in the same file?
I'm pretty sure the DVDs of some TV shows (for example Babylon 5) have the live action sequences shot on 24p film then telecined up to 60i while the VFX sequences are on as native 60i. Is this only possible if the sequences are in separate GOPs or can you mix types frame by frame, field by field as you wish? If you could do it this way, it would probably result in the best playback on DVD Players/TVs. But I don't think it's possible.
Personally, what I'd do is use AVISynth to do a very slow very high quality bob-deinterlace the 60i to 60p, then do a very slow high quality frame interpolate up to 120p. Then I'd decimate by picking every 5th frame back down to 24p. Then mix with the 24p stream. But that's just because I HATE interlacing, and it's probably overkill. I'm sure someone will tell me I'm wrong too.
What you could also do is interpolate the 24p up to 30p (I.E., every group of 4 frames would have to have one new interpolated frame to make 5), then just do a straight double to 60p then throw out every other field to make a faked 60i. Then edit with the native 60i as needed.
I dunno. Put it this way - for the best quality, I don't think you're going to be able to do it inside Vegas. There might be a way to force Vegas to do it if time & speed is more important than quality, but I don't know what it is.
Moral of the story - shoot progressive, unless you want to do slow-mo. Actually, moral of the story - move to Europe, over here, all we have is 25p and 50i. Easy multiples!