24P vs. 60i for Broadcast and DVD

J

jsaint

Member
I am heading up a film shoot with 3 DVX100's that will be for broadcast initially and then will be made available on DVD. I thought I understood the 24P concept until I read some stuff on this forum that confused me.

I thought that when you shot 24P the camera is capturing 24 full frames per second (as opposed to 60 half-frames with other cameras) and then the camera recorded it onto the DV tape as 60 half-frames per second, which is my understanding of standard NTSC.

What I am reading is that you can actually use the 24P as 24P for either film transfer or DVD output. Does it actually record 24 full frames per second onto the DV tape? Do you have to capture into FCP-HD as 24P to keep that?

Thanks for the help and thanks Rush for the help in getting the camera!
 
Re: 24P vs. 60i for Broadcast and DVD

The CCD captures 24 full frames..but they're recorded to tape as 60i. You're right about that. The NLEs that support 24P native editing know how to remove the conversion, and extract the true 24 frames per second. When you're finished, you can either use the 24P edit (when making a DVD, for example) or you can re-add the pulldown, to the entire project, for recording to tape.
 
Re: 24P vs. 60i for Broadcast and DVD

yes it does, you can edit true 24p (you have to shoot 24p advance) and see footage in real time on your computer and TV monitor, if your computer is fast enough. G4s are strong enough.
 
Re: 24P vs. 60i for Broadcast and DVD

OK, so there are two versions of 24P then, one that records onto the DV tape in true 24P and one that does the pulldown to NTSC, right? That makes sense. Is this a new feature with the DVX100A? I guess we will want to shoot this stuff using the conversion to NTSC, or I guess the computer can convert it when we export, as long as we set the deck right, is that right?

Oh, that makes me need ask if the DSR-11 can read the 24P advance tape?

Thanks so much for the help.
 
Re: 24P vs. 60i for Broadcast and DVD

Jsaint- there are two versions of 24p....24p normal and 24p advanced...both record a 29.97 interlaced video onto your miniDV tape....the difference is in the cadence of the pulldown.

They will look basically the same but what you have to decide what the final product will be (i.e. what format?). If you'd like a 24p DVD or you are planning on a transfer to film then the 24 advanced is for you.

If you are always staying in "Video NTSC land" with no plans for a progressive DVD or filmout then 24p normal is for you.

Both 24p normal and 24p advanced can be edited in a 29.97 timeline or a 24p timeline. However, if you are editing in a 24p timeline your final output is better using 24p advanced since you return to your "original" progressive frames.

check out www.adamwilt.com/24p/index.html#24Recording

it explains it very well there

sounds like you are eventually going to DVD format....so the question becomes progressive DVD or interlaced? If the answer is progressive then you should shoot 24p advanced.

hope this makes sense
shm
 
Re: 24P vs. 60i for Broadcast and DVD

I wish the whole myth about having to be 24pA to go to film or progressive DVD would just go away. 24pA is designed to work 24 frames native when working at DV25 resolution and capturing over FireWire without suffering a decompress/recompress step -

If you are shooting the DVX100 with the intention of creating a progressive DVD and can only work in a DV25 only resolution over FireWire, then shoot ADVANCED.

But there are plenty of systems that can work native 24fps from either pulldown during capture and once in the application as such can be used to go back to film or create progressive DVD regardless of pulldown cadence - ADVANCED or NORMAL.

I have done filmouts from NORMAL and ADVANCED using the DVX100 camera, the decision to shoot one over the other was all dependent on the editing system and its capabilities to work with either over whatever I/O I had available - DV/FireWire or SDI.

Michael
 
Re: 24P vs. 60i for Broadcast and DVD

*I* wish the whole myth of 24pA being recorded to tape in "true progressive" would go away, too.
 
Re: 24P vs. 60i for Broadcast and DVD

It's not true progressive, but it's as close as we can get in NTSC :-/

It's closer to being progressive than a standard 3:2 pulldown...
 
Re: 24P vs. 60i for Broadcast and DVD

Okay, what exactly is "progressive" mean/add to the video universe?

jmf
 
Re: 24P vs. 60i for Broadcast and DVD

With progressive, rather than displaying half of the frame, alternating with opposite lines, an entire frame is displayed.

The DVX captures progressively (if you want it to) but, because it has to become NTSC, is transferred to tape in the standard 60i format (60 fields per second).

I'm too tired right now (at work :P) to explain it more clearly...but if you do a search on the web you'll find out all you need to know.
 
Re: 24P vs. 60i for Broadcast and DVD

Thanks for all of the comments. It looks like I am not the only one benefitting from this thread, which is the way forums are supposed to work. I do understand this issue now. Thanks for all of the help DVXusers!
 
Re: 24P vs. 60i for Broadcast and DVD

[quote author=MichaelP link=board=nws;num=1090363437;start=0#6 date=07/25/04 at 19:46:03]I have done filmouts from NORMAL and ADVANCED using the DVX100 camera, the decision to shoot one over the other was all dependent on the editing system and its capabilities to work with either over whatever I/O I had available - DV/FireWire or SDI.

Michael[/quote]

Michael, would you mind sharing how you're doing 24p through SDI? What editing system, and the steps would be nice. I shoot 24p, use FCP and would love to go SDI through SDI and lose the firewire. Any help would be appreciated.
 
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