24P - 29.97 and NLE

bodaphoto

bodaphoto

Well-known member
I have some questions about the 24P thing.

This is my understanding..... when shooting in the 24P mode to tape, the Camera captures at 24 frames a second. Then it does some sort of interpolation and converts it to 29.97 as it records it to tape, NTSC video is recorded at 29.97...Right? Then once you are done editing and you make a DVD(it then becomes 29.97) to be played on NTSC dvd players, it is played at 29.97.

My question is when you load it into an NLE, say Vegas for example and it has the capture mode for 24P, what does it do to your video that say Pinnacle Liquid does not do? What is it that 24P and the programs that capture it at 24P do, when your end product is eventually converted to 29.97 on video or DVD?

Is the difference when you capture directly to a hard drive? Is the need for 24P when your project is being converted to film?

I am mainly asking this because I will be building another computer and it is possible I may also get another program such as Vegas or Avid.
 
Re: 24P - 29.97 and NLE

Your NLE, used properly, will remove the pulldown from the recorded footage. You are right in say that your 24P is recorded as 29.97. When it is captured, it is converted back into 24P. You edit it that way. You output to DVD or tape whichever way you want, 24P or 29.97. It depends on your needs.

Other wiser and more experienced people may of course correct me on this, but I think I'm right.
 
Re: 24P - 29.97 and NLE

Just to be technical, it *never* gets laid back to tape as 24P...it's still 60i mathematically, it's just either laid down with a standard 3:2 pulldown, or an advanced pulldown.
 
Re: 24P - 29.97 and NLE

So the camera puts the info on the Tape that it recorded it in 24P. The programs that recognize that (Vegas, FCP, Avid, Adobe) convert the footage back to 24P.

Yet, when you output, my understanding is on DVD/VHS here(US, Canada, Japan) it is NTSC which is 29.97, that is what all video plays at DVD or VHS. What is the advantage and what does it give when DVD is your final output?
 
Re: 24P - 29.97 and NLE

the 3:2 pulldown basically takes your 24P footage and plays it as smoothly as possible in 60i, which is inherrently needs to be if you're watching it on an NTSC television.

The reason you'd want to have a true 24P master is for DVD purposes, or for a film-print. But even your DVD that has a 24P native MPEG2 file on it will still be converted by your DVD player in real time to 60i, using a 3:2 pulldown.
 
Re: 24P - 29.97 and NLE

Thus, the programs that "Edit in 24P" continue the smoothness. OK. I understand fully now.

Thanks Guys. :D
 
Re: 24P - 29.97 and NLE

Yeah, I think the part you were missing is that you can finish your DVD in 24P mode.

The DVD player will automatically insert pulldown to convert it to 60i (or 29.97), but the data on the disc will be 24P.

That gives you three advantages:
1) You can fit 20% more space on the disc at the same compression ratio, or
2) You could use a lower compression ratio and get better quality.
3) If you play back on a progressive-scan display, you can skip the whole pulldown process entirely and see the 24P played back at 24 frames per second.

Also, editing in 24P means that it's a lot less render-intensive (i.e., projects render faster) and there are fewer frames for rotoscoping/compositing, etc.
 
Re: 24P - 29.97 and NLE

Barry you are the man!!

you just brought a whole new game to my court. :)

thank you
 
And Now... Oops.

And Now... Oops.

Okay, how cool.

Cue inexperienced cameraman shooting 30P normal aspect ratio one day, then accidentally shooting day 2 on 24PA Anamorphic Squeeze...

Am I doomed? Or can I somehow get all this to play nice in a 24P Anamorphic sequence in Final Cut Pro HD?

me=bonehead.
 
Re: 24P - 29.97 and NLE

The best solution methinks would be to put it all in a 60i timeline - have the 24P footage apply a regular 3:2 pulldown, and the 30p footage will play perfectly in 60i.

Converting 30p to 24p is next to impossible, if you want smooth results, without slowing down the footage :-/

So definitely go with the 60i route.
 
Re: 24P - 29.97 and NLE

ok ok.....I need in SIMPLE terms... How do I shoot a film, and then maintain the 24p look. Because OF COURSE I want my film to look like film, so I would like to maintain 24p... I may sound stupid, but hey, you can't see my face. SO I DON'T CARE! lol :) Someone care to explain in laymens terms. Thanks!
 
Re: 24P - 29.97 and NLE

If you've shot the footage in either 24P mode, it'll look like 24P footage with a pulldown (which is the exact same look that Hollywood movies have - they shoot at 24 frames per second, but on our NTSC TVs, we're seeing the footage with a 3:2 pulldown, in 60i).

So shoot in 24P, cut it however you want, and it'll look the same as any other Hollywood production (motion rendition-wise, of course). The way to maintain the highest quality is to shoot in 24PA, and cut in a true 24P timeline, and then output to tape with a standard 3:2 pulldown.
 
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