24p questions

[John Mercer]

"Are you sure that's right about Avid requiring the Mojo box for output? I didn't know the box had anything to do with 24p."

I certainly remember a lot of discussion about it on the Avid forums - people being very surprised that they could capture advanced pulldown, but not output it to tape without Mojo. Maybe they've updated it - but I've not heard anything since.

Have you tried outputing a 23.976 advanced pulldown sequence to tape with your systems? I work in PAL land so I have no chance to put it to the test.

I have Xpress Pro and Mojo and I think there is certainly a need for Mojo - at least for me. It gives you 1:1 uncompressed and allows you to mix native DV with 1:1 titles, graphics and FX - so that everything remains very high quality and does not suffer degradation by using only the DV25 codec. I've noticed a big difference in quality of both DVCAM master tapes and DVD.

Real time fx for software only are on the composer monitor only - everything has to be rendered for blue dot output. Mojo gives you perfect studio monitor sync with your timeline - no firewire lag - with realtime full quality fx output - makes a huge difference for complex edits.

All in all it's one of the best pieces of kit I've bought in a long time.

[Valeriu Campan]

I noticed on a side by side spec sheet (PAL & NTSC) that the XL2 PAL camera has only 50i and 25p format. The NTSC version has 60i, 30p, 24p options. Is it correct? Why not the 24p option for the PAL world?

[Rainer Hoffmann]

Valeriu,

they don't bother with 24p because 24p and 25p are almost the same. If you shoot for TV, 25p is fine for PAL.

If you shoot for the big screen you just slow down the movie by about 4%. The difference between 24 fps and 25 fps is not noticeable. However, you have to take care about the sound in that case.

Compare the running time of a movie you saw in the cinema with the running time of the same movie on a PAL-DVD. It is approximately 4% shorter on the DVD because it was shot at 24 fps and is now replayed at 25 fps. But you won't notice the difference.

[Rob Lohman]

Another reason is that this would have been almost impossible
to implement technically due to the restrictions of the DV format.

And as Rainer indicated you really do not need it. If you really
care about film output talk to your film house and ask if they
need 25 fps for a european release or 24 fps.

[Valeriu Campan]

I am aware that PAL requires 25p or 50i. Also I know that for theatrical release you can "sort of" get by adjusting the length/pitch of the soundtrack, but then why others bother - Sony, Panasonic, Panavision, Kinetta, Viper... making cameras with 24p option? And for the same reason, Arri Aaton, Moviecam should also drop the dreaded/useless 24fps and go 25fps.
Maybe Canon as always is ahead of the pack and we are witnessing the birth of a new standard?

[Chris Hurd]

This standard is not new. Panasonic did it first, with their DVX100E having 25p instead of 24p, in the PAL model.

Who could tell the difference between 25p and 24p? Nobody; not humanly possible, so it's no big deal I think.

[Barry Green]

24P is not useless, it's perfect for NTSC televisions (which make up about 70% of the TV's in the world).

25P is perfect for PAL television.

25P and 24P can be converted to each other with very little hassle.

Remember, these cameras (DVX and XL2) are not designed for film, they're designed to make video that looks like film, that plays back on an NTSC or PAL television. 24P is perfect for NTSC playback, since it emulates the look of 24fps film transferred to NTSC video. 25P works perfectly with PAL televisions.

[Valeriu Campan]

Still I don't understand why the PAL users have to go through "the little hassle" of making their projects 24fps compatible for theatrical release. Looks like Canon decided to do a pre-emptive strike in the war against the 30% of the non-NTSC infidels.
The 24p option in the NTSC model is there solely for the possibility of using your project for theatrical release. Still, why higher end cameras from Sony, Panasonic, Panavision, Kinetta, Viper have the other options? Is it so expensive to implement it? I see it only as a software/firmware issue. Why denying the rest of us the same smooth passage, puzzles me.

I have recently shot a feature on 50i and the producer is in the process of preparing it for film conversion.

[Don Berube]

Valeriu Campan writes:
>>>>>>>>Looks like Canon decided to do a pre-emptive strike in the war against the 30% of the non-NTSC infidels.

Eh,,, huh?

>>>>>>>>The 24p option in the NTSC model is there solely for the possibility of using your project for theatrical release.

Not 'solely' for that. It's also provided for those who will never do a film-out but want the motion signature of 24P.

>>>>>>>>Still, why higher end cameras from Sony, Panasonic, Panavision, Kinetta, Viper have the other options? Is it so expensive to implement it?

Exactly what options are you referring to?

>>>>>>>>I see it only as a software/firmware issue.

What exactly do you see as a software/ firmware issue? It would be helpful if you were to clarify your statements.

Why denying the rest of us the same smooth passage, puzzles me.

What exactly is it that you feel you are being denied?

- don

[Thomas Smet]

us using NTSC still have to do a process to get 24p. The camera isn't actually putting 24p onto the tape but a 30i with 3-2 pulldown. Once we capture the footage we either have to convert the 30i with pulldown to full 24p or use an editing package that does it automatically for us.

NTSC- 30i with 3:2 pulldown frames - convert those frames to 24p
PAL - 25p frames - slow down to 24p.

When movies are shot in 24p they need to be converted in different ways to NTSC and PAL. For NTSC 24p uses a 3:2 pulldown method where you end up taking fields from different frames to get a pseudo 30 interlaced frames per second. For PAL the 24p movie needs to be sped up to make it 25p. The DVX and XL2 are basically doing the opposite of that process.

As for why do $100,000.00 cameras do this and not my $5,000.00 camera just think about it for a second. Do you really want to pay an extra 10 or 20 thousand for the XL2 to have advanced chips to allow you to shoot whatever frame rate you want? It takes a lot of hardware for those highend cameras to do that hence the higher price.

You know in some ways the PAL camera is actually better because you get a little more resolution per frame and you deal with full 25p frames from the begining instead of having to apply a reverse 3:2 pulldown. With the pulldown and NTSC if we shoot 24p video it will look kind of funky on TV's. With 25p it will always look goof no matter how you shoot or what format you view it on. The only downside to 25p is having to slow down the audio by 4%. If you don't want the slight pitch change you could always time compress the audio.

Finally if you only plan on shooting movies with your XL2 why not get a NTSC model and a cheap power converter? That way you can have 24p. You could always get 25p if you really needed to also. You would just do the opposite and speed up your 24p video to get 25p to view on your TV.

[Valeriu Campan]

<<<-- Originally posted by Thomas Smet :

As for why do $100,000.00 cameras do this and not my $5,000.00 camera just think about it for a second. Do you really want to pay an extra 10 or 20 thousand for the XL2 to have advanced chips to allow you to shoot whatever frame rate you want? It takes a lot of hardware for those highend cameras to do that hence the higher price.. -->>>

The NTSC model doesn't seem to cost extra 15-20k with those advanced chips to have that third extra option. Just machining and manufacturing a different shell for the PAL camera and a switch seemed to be more cost effective for the bean counters.

Having said that, for my next major project, a PAL XL2 has already been ordered (a dumbed down PAL model... huh...) and I feel that a second one will be on the cards for safety/backup reasons. By the way I will sell my original XL1 (PAL). Any takers out there??? Hard to believe!

[Rob Lohman]

As I stated earlier Valeriu, the DV specifications DO NOT allow
for the format you are describing, nor does any NLE have a
template / profile for it. So it's not "just" Canon's decision.
I don't know of any PAL camera that "has" 24p.

So I assume you would want this PAL 24p for the benefit of
the higher resolution to go out to film? Will you really be going
to film?

[Martin Munthe]

<<<-- Originally posted by Valeriu Campan : Still I don't understand why the PAL users have to go through "the little hassle" of making their projects 24fps compatible for theatrical release. -->>>

Since every post house in the PAL world is set up to handle everything at 25fps (with pitch conversion on optical prints being a standard process done in the print process or the "film out" process) it's a MAJOR hassle to shoot 24fps and expect it to be a smooth workflow. In europe almost everything is shot 25fps. That includes 16mm and 35mm. It's so much easier to handle 25/50 based projects in the postproduction process. I bet a lot of americans would LOVE to not have to go through the 2:3:3:2 pulldown everytime they make something for the big screen. It's so awkward. The best thing would to let go of the old analog 24fps standard and just shoot 25p, 30p and 50/60p. It saves time and money.

I was talking to the matchcutters and tech people at Technicolor and Manhattan Transfer, New York (they did 25fps dailies for us on a 35mm shoot) and they where so envious of the simplicity of the PAL 25fps/50i setup.

[Rob Lohman]

Martin: I totally agree. I think Valeriu is just wanting a higher
resolution at 24 (native) fps. Probably not aware of how much
"work" the pulldown process is in the XL2 24p mode for example
(speculation).

[Thomas Smet]

you are not understanding the process of creating 24p on these cameras. No the NTSC doesn't cost an extra 20 thousand. The point we are making is that in order to get a camera that can do 24p, 25p, 30p, 60p, and 60i you have to have some advanced chips that cost a lot. For NTSC we are fortunate that there is a process to calculate 24p from 30. The camera isn't actually shooting 24p in NTSC. It is shooting 30i that is in a slightly different field format so when we apply a 3:2 pulldown we get a pure 24p. For PAL there is a different process to get to 24p. This isn't Canon's or Panasonic's fault. Blame the people who decided to make these video standards 50 years ago. The SONY Cinealta camera has chips that can do every format because it was designed to and costs a lot more to do.

What format would you rather have Canon and Panasonic use?

Clearly 25p Pal cameras cannot use 3:2 pulldown because then you would have 20P which would not be any use to anybody. If 3:2 pulldown doesn't work then what is there to use for PAL?

You have basically two options for PAL cameras.

1. Slow it down by 4% which would not be able to be done while shooting live.

2. Have advanced chips and camera design that could basically process video live at any framerate. Very expensive.

You can see why to get 24P in PAL it would be very hard and expensive. I'm sorry that is the way it is. I wish there wasn't PAL and NTSC but there is and we have to deal with it. Lucky for us NTSC users there is a hack work around to get 24P live.