24pa ?

safarijoe

safarijoe

Well-known member
I'm sure someone has already answered this somewhere but I can not find the answer anywhere. I've looked at the movie, read the brochure, checked the website and even did a search. I still didn't find it. So I'm going to ask. Will the HVX do 24pa in either HD or SD or both?:huh:
 
In HD, no need for 24pa when you can actually do 24p. :thumbsup:

Not sure about SD though. I would assume that's the only way it could do it, but not sure.
 
In 720p, as Ryan said, there's no pulldown at all -- it's straight-up 24p.

In SD and 1080/24P HD, it does both 2-3 and 2-3-3-2 pulldown (so yes, it will offer both 24P and 24PA modes). It shoots 24p in every mode that the camera offers, DV/DVCPRO25/DVCPRO50/DVCPRO-HD 720p/DVCPRO-HD 1080p.
 
This is news to me - and great.

So if you record in 720p 24p - you get exactly 24 frames/sec? - no pulldown needed. This means none of the "loss" associate with the pulldown in 2:3:2:3 24p

am i understanding this correct?
 
but if you use p2 cards, it isnt going through firewire at all. but i assume that it'll write to the p2 cards as 1080/60i anyway. but how come 720p doesnt go through firewire as 720/60i? is it cuz there is no 720/60i? But then, doesnt all 24p footage employ a pulldown (2:3 and now 2:3:3:2) in order for it to be displayed on an NTSC television, making it 60i? I'm not questioning anyone's knowledge here... I'm trying to learn so please don't be insulted.
Thanks!
-Paul DV
 
So if you record in 720p 24p - you get exactly 24 frames/sec? - no pulldown needed. This means none of the "loss" associate with the pulldown in 2:3:2:3 24p

am i understanding this correct?
Click to expand...
Yes. 720p is stored as progressive frames, and it stores (on P2) only the frames that it needs. So if you shoot 24 frames per second, the file on the card will have only those 24 frames, no pulldown, no duplicate frames, etc.


but i assume that it'll write to the p2 cards as 1080/60i anyway.
Click to expand...
That is correct. DVCPRO-HD supports 1080 recording only in interlaced (just like DV only supports standard-def recording only in interlaced). To put progressive-scan within an interlaced signal, they use the 2-3 or 2-3-3-2 pulldown systems.


but how come 720p doesnt go through firewire as 720/60i? is it cuz there is no 720/60i?
Click to expand...
Yes, there is no such thing as 60i. However, the 720p signal going out the firewire port is always sent as 720/60p. There is no "pulldown", but there are duplicated frames to make up the difference. So if you shot 720/30p, the firewire would output 720/60p, and each frame would be duplicated. If you shot 720/15p, the firewire would again output 720/60p, with each frame shown four times.


But then, doesnt all 24p footage employ a pulldown (2:3 and now 2:3:3:2) in order for it to be displayed on an NTSC television, making it 60i?
Click to expand...
Yes. That is exactly true.

And all high-def broadcasts in the US, AFAIK, are being done in 1080/60i or 720/60p. The broadcast standards do allow for directly broadcasting 1080/24p and 1080/30p and 720/24p and 720/30p, but I don't believe anyone bothers, they just broadcast 1080/60i or 720/60p. Films get broadcast using the same pulldown sequence as they've been using for NTSC.
 
Thanks for clearing that up Barry. So editing programs are going to have to have some kind of support for duplicate frame removal with 720p footage?
Thanks again!
-Paul DV
 
If you're capturing the footage via streaming, then yes they should have some support for removing the duplicate frames. FCP-HD already has a software Frame Rate Converter program; I'm sure other editors will as well.
 
And I'm sure that with the 720p it wont be a problem cuz the Varicam has been out for some time now. Just out of curiosity... what do the "Hollywood" HD cameras, the cinealta, the genesis, etc use as a pulldown method when they capture to tape? Do they use 2:3? I was looking on brochures and all they say is it does 24p among other others but no mention of the type of pulldown. I assume 24pA is somewhat new. I thought I remembered reading that Panasonic came up with 2:3:3:2.
Thanks again Barry, you're awesome. I've been using your book while I've been shooting my two films. Great reference. That book is really amazing.
-Paul DV
 
Glad you like it! It's always nice to hear when someone is helped by what you've done...

Okay, for the CineAlta -- there is no pulldown. The CineAlta uses a recording system that Sony calls PsF -- Progressive/Segmented Frame. They split the progressive frame into two fields, then record them as fields, but they record it on a modified PAL drive that they slow down a little -- so it actually records 48 fields per second. So in effect it's the same basic technique as the DVX uses for 30p -- a progressive frame split into two fields and recorded directly -- but they actually slow the tape down to 48 fields per second instead of the 50i standard of 50 fields per second.

Don't know what the Genesis does...
 
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