on understanding 24p

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Hi guys, I've been editing for about a year now and have been working with the dvx100a for about 4 or so months. I'm editing in vegas and have a couple of questons on 24p.

If I shoot something in 24p on the dvx, what happens if i take that tape and play it back on a camcorder that doesn't support 24p? will it cause a problem in frame rate?

When vegas says to render something REMOVING pulldown, does that mean it's going from 30fps to 24fps or 24fps to 30fps? If I capture footage at 24fps, do I need to remove pulldown? When exactly do I need to remove pulldown?

These are my main questions. I would be super appreciative if someone could help me. Thanks.

ronnie
 
Re: on understanding 24p

also, for some reason i'm scared of 24pa mode. i feel i haven't comprehended it enough to actually use it. why is it better?
 
Re: on understanding 24p

You can play back the tape on any camcorder, because it's recorded to tape according to the DV spec.

Vegas will automatically remove pulldown in a 24p project.

24pA encodes its pulldown in such a way that's easier to extract the original 24p frames from the 60i tape.
 
Re: on understanding 24p

not that the reasoning may matter to anyone, but I belive that even when you are shooting 24fps it is being converted and recorded on the tape at 60i.

although I could be wrong.. I think it's happened once before..... ???
 
Re: on understanding 24p

For pulldown and dvx100 in general go to http://adamwilt.com/24p/
One of the best links this forum offered me.
It explains in graphic detail how and why the pulldown is applied. One thing i am glued to is 24pa and wondering since couple of interlaced fields are left on their own why do the frames in the pattern of 2:3:3:2:2:3:3 appear longer and shorter? As stated on Adam's site  http://adamwilt.com/24p/24pAdvanced.gif
we recover all frames from the interlaced material without the use of the extra frames. Why longer durations then? Do we omit them ? Can we? Also is premiere pro friendly to dvx's 24pa footage and the sync problem?
 
Re: on understanding 24p

[quote author=Cuppajoe Films link=board=Events;num=1089383198;start=0#5 date=07/09/04 at 20:04:46]not that the reasoning may matter to anyone, but I belive that even when you are shooting 24fps it is being converted and recorded on the tape at 60i.  

although I could be wrong..  I think it's happened once before..... ???[/quote]

You're correct on this one. It's what pulldown is all about.
 
Re: on understanding 24p

The longer (duplicate) frames are there because it has to change 24 fps to 60 fps and keep the same timing. When going into some editing systems (such as FCP) it will remove these duplicate frames so it's 1:1 24fps. When you go back out to most video (not DVD's) you'll have to add 3:2 pulldown to the images.
 
Re: on understanding 24p

Ahh right so 4 frames equals 5 frames of video which is 10 interlaced fields and while conforming the progressively captured footage to ntsc tape we insert extra 2 fields of video to keep the same duration. Blah and that is where the pulldown comes in and comes out... whoosh thanks.
Also the 2:3:3:2 pulldown is the one you are talking about.
 
Re: on understanding 24p

24pa is recorded with 2:3:3:2 pulldown. This means there's no frames split over fields (cleaner image) but is not the smoothest to watch. Because it has duplicated full frames it tends to stutter slightly.

3:2 is the process done for film to video transfers. (And the same as 24p mode) The frames are expanded to cover the same time in video and will be over fields for a smoother and more consistent speed. When you're all done with your video and want to output it to video tape for display this is the pulldown to add. If you just want to archive it to video then you could go 2:3:3:2 to keep pure frames.
 
Re: on understanding 24p

Let me finalize this if we remove the pulldown from advanced captured footage then we are skipping the duplicate frames altogether correct? Going from 10 interlaced fields back to 4 frames. Now this stutter effect you are talking about... i am trying to understand this since we recover all 4 original frames from the source interlaced material via 2:3:3:3 pulldown removed, why do we still stutter or do we?

My thing is to capture 24pa into NLE (vegas) removing the 2332 pulldown then out sourcing the material onto a dvd keeping all the original frames. Am i up to date? heh Thanks Scott.
 
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