24p questions

[Adam Lawrence]

you would figure by now (considering that the release date is right around the corner) that Panasonic will have posted some screen shots from their
new AG-DVX100.

Would anyone have any info on this?

[Don Berube]

I shot some quick test footage with the DVX100 a couple weeks ago at the LA DV Show, about 20 minutes worth. Even though I did not get deep into the camera's image setup control, I was pretty impressed with the overall image quality. Upon playing it back, I noticed that no TC was recorded onto tape - probably due to the fact that this was still a prototype model. I'm sure that the production models will record TC. Did a capture onto my laptop for kicks, even though the software I used at the time (Sonic Foundry's Vegas Video 3.0) did not have any 24P capture preset available. Basically what was created was a 29.97 DV .avi file that has a 3:2 pulldown look, like 24fps film xferred to interlaced NTSC. The 16:9 image was captured properly by the software and played back well in that aspect ratio. Sound recorded by the built-in mic seemed decent as well.

I will be doing some more test captures with FCP 3.0 on my G4 shortly. I'm sure that FCP will do an excellent job capturing the 24P test footage. Will keep you posted.

I'm sure Panasonic will be publishing some test images/ footage soon. In the meantime, I am very much satisfied with what I can do on the XL1S, especially with some filtration and tweaking in FCP. Will be shooting with the P+S Technik Mini35 on an upcoming project, am looking forward to it!

- don

[Rob Lohman]

This means you will have to do a 3:2 pulldown to get the original
24 fps footage, right? I hope they deliver presets or software with
their camera because 3:2 pulldown can be tricky and yield horrible
results if done wrong.

[Clayton Farr]

You can edit it as 60i (24p capture with 3:2 pulldown) straight out of the camera - no 3:2 removal necessary. (Akin to editors cutting projects that were shot on film then telecined and will be only shown on video/broadcast - ie: tv shows). Depending on how finicky you want to be you could just keep an eye on whether you are cutting on a 'split' frame or not.

So I don't think there is any worry about being able to use the footage straight away for most projects. The issue of removing the pulldown would come up if you wanted to do composite/fx work at the native 24fps or were making a transfer to film. But given that the camera produces a standard 3:2 pulldown (in addition to another custom pulldown mode) it shouldn't be any problem to remove with After Effects or the like.

2 cents,
Clayton

[Clayton Farr]

And oh yeah - some camera frames would be *great*.

Donald could you post (or post a link) to some examples of the stuff you captured. Like some examples of both the image static and in motion (to get an idea of quality of progressive image) - ideally as an uncompressed PICT or TIF or the like?

Clayton

[Rob Lohman]

I prefer the native DV stream :) ... oh well... You are ofcourse
correct that you can edit in 60i... BUT. If you do so, you are very
likely to destroy the 3:2 pulldown process because you are
editing on frames that should not be there. If you then go and
do a 3:2 pulldown in the end you will not get the results. If
you want to have 24 fps I believe you have to do 3:2 pulldown
on the source material, not the edit output.

[Clayton Farr]

<<<-- If you want to have 24 fps I believe you have to do 3:2 pulldown on the source material, not the edit output. -->>>

Yeah, certainly. Unless you keep 3:2 cadence throughout the edit (assuming you would need it for a final 24p output or some other purpose.)

Which as you mention can either be done by working on a system that would allow removal of 3:2 natively in the NLE (higher end AVIDs now and maybe FCP later) or you could just try to restrict your edits to timecodes with a multiple of 5 in the frame count. 0, 5, 10, 15, 20, 25, 30(0) (Info per Panasonic Rep Stuart English on 2-pop boards.)

This would perhaps be a bit limiting but may be an inexpensive (free), readily available solution if you must keep cadence. But again I'm not sure how critical cadence is if the work is solely intended for video/DVD/broadcast - but then again who wouldn't want to make a film print if Miramax offered... ;)

So in short, you could work wih the material as soon as you had such a hot little camera in your hands, but it will be nice when 24p native editing becomes more common - if nothing else it would cut your rendering down by 20%!

Any one else have any more/other info to either support or correct these notions?

Clayton

I posted this question in another thread, but it got lost as another discussion took over:

What's the advantage, if you're shooting for NTSC broadcast, of using the 24p mode instead of 60i?

What about if you're outputting to DVD? Is there an advantage of 24p over 60i?

Or is 24p really just mainly for transferring to film?

There are a couple "Advantages" that may or may not apply to you:

1. Look and Feel. With 24p and a 1/48th shutter speed there is more motion blur and bit of a loss of detail that are one of many qualities found in Film. If you like the look of 24p then you might prefer to shoot with it. If you don't you probably won't want to.

2. Progressive Scan. With 24 or 30p, you are shooting full framed progressive images instead of interlaced. On DVD playback with a Progressive Scan Monitor this too can be a better image with more vertical detail than you'll find in interlaced images.

3. Reducing Post Production rendering times. With 24 fps you'll need 20% less rendering if you are doing things like compositing, effects, or any other major rendering tasks. For some this can result in days less rendering time.

[Don Donatello]

i don't have DVD yet ...

so are DVD's made at 24fps and then when it plays back it adds the 3:2 ???

i don't see how there would be 20% less rendering for a NTSC broadcast tape ???
because if shoot at 24P and edit it in true 24fps at some point you must render out a version with the 3:2 so it will play on a NTSC monitor ??? seems like it would have to render every frame ?

or if you shot 60i then took it and changed it to true 24fps and edited in 24P .. you must still at some point render out a version with 3:2 added so it will play on a NTSC TV ???

or even if you used the DV film maker ( with 24P dvx100) which just pulls out the 5th frame ( no re-rendering ) at some point it for it to play on a NTSC monitor it must render out with 3:2 added ??

not quite sure how you would save 20% rendering time for a NTSC version ??

Rendering 3:2 pulldown is much faster than rendering complex 3d effects, Composites, Color Correction or Green Screens.

DVDs can be encoded with 24fps Progressive. The DVD player is then responsible for either 3:2 pulldown for NTSC or proper formatting for a Progressive Scan TV.

[Rodger Marjama]

<<<-- Originally posted by aaronscool : Rendering 3:2 pulldown is much faster than rendering complex 3d effects, Composites, Color Correction or Green Screens.

DVDs can be encoded with 24fps Progressive. The DVD player is then responsible for either 3:2 pulldown for NTSC or proper formatting for a Progressive Scan TV. -->>>

When producing 24P for DVD, flags are encoded into each 4 frame segment corresponding to the 2:3 pulldown sequence. If the DVD is played back in progressive mode, these flags are ignored and the DVD playes at 24 fps. If the DVD is played in NTSC mode, at every frame where a flag is found it will replayed that frame once, thereby creating the 30 fps (29.976) playback need for NTSC.

One of the great advantages to using 24P in DVD is the FACT that you will increase the allotable file size on any given DVD format you are working with. This means more playback time, or higher quality -- your choice! When you see 24P DVD playback on HD and compare it to a DVD that was encoded from NTSC using the 2:3 pulldown, there is a remarkable difference and much improved viewing experience with the 24 fps DVD.

-Rodger

Other than motion blur and rendering time, are there any further advantages/differences to shooting in 24p and playing back on a NTSC monitor (either with a DVD or outputing to 60i on a tape)? does the extra vertical detail translate to the NTSC broadcast at all?

Also, what happens when you go from 24p to a 3:2 for NTSC? It becomes 60i?

Thanks. And thanks for the above responses as well.

<<<-- Originally posted by donking! : Other than motion blur and rendering time, are there any further advantages/differences to shooting in 24p and playing back on a NTSC monitor (either with a DVD or outputing to 60i on a tape)? does the extra vertical detail translate to the NTSC broadcast at all? -->>>

Not really if you intend to stay exclusively in NTSC for your output and you don't care too much for the 24p motion blur then a better choice would be 30p. This is frame/feild compatible with NTSC without pulldown and will get the same increase in resolution as 24p.

<<<-- Also, what happens when you go from 24p to a 3:2 for NTSC? It becomes 60i?-->>>

Yes.

[Stuart English]

Some more 24P clips are available to download at

http://www.dvinfo.net/panasonic/media

To be honest, I don't know if these are 24P or 24P ADV
clips ( I meant to read the matadata off the camera display
this morning but brought my daughters 1st brithday party
tape instead - so I'm sure someone can work that out by
running a Marcus's 24p conversion program on it.

The files are large, smallest is 17Mbps (short flight) - this
is a truncated version of mainflight. So maybe try this first
and the others later.

The weather in Santa Barbara was bright, so high contrast
lighting conditions, the Cine-like Gamma was set ON. The
camera was a pre-production unit, so still not 100%
representative of an actual unit.

As I mentioned at the beginning of this process, we would
normally not post a clip from a pre-production camera, but
as we were specificly asked to do so, we have obliged.

Regards,

Stuart English
V.P Marketing
Panasonic Broadcast