[MacDV] Re: 23.98 fps when using Cinematize or DVDxDV

[whoisquilty]

Aaron -

Thanks for your advice and the link. This is making some sense (this
is a new realm for me).

With regard to this:

> (BTW, I'm curious why one would want to create a MOV file with a
> frame rate of ~30 fps if there really are only 24 frames per second
> in the original movie.)

I'm not sure that I have a choice in the matter. I need to edit the
converted video file. On importing into Final Cut Pro, FCP tells me
that the frame rate is 29.97 (when Quicktime tells me that it's ~24).
If I change the sequence settings in FCP to 24, the sequence needs to
be rendered. Leaving the frame rate at the default 29.97, it doesn't.

Will FCP adding the extra frames give me "jerky" video when I finish
the project to DVD?

Jer

On 1/11/06, Aaron <macuser at aarons.fastmail.fm> wrote:
> >Date: Tue, 10 Jan 2006 16:32:34 -0800
> >From: "Dennis R. Cohen" <drcohen at mac.com>
> >To: macdv at listserver.themacintoshguy.com
> >Subject: [MacDV] Re: 23.98 fps when using Cinematize or DVDxDV
> >Reply-To: "A place to discuss digital video on Macintosh." <macdv at listserver.themacintoshguy.com>
> >
> >On 1/10/06 at 5:46 PM, whoisquilty <whoisquilty at gmail.com> the following
> >electronic message:
> >
> >>Hello -
> >>
> > >I keep getting Quicktime files with 23.98 FPS when I convert a DVD to
> > >MOV with both Cinematize and DVDxDV. I'm trying to create a NTSC file
> >>from the DVD. The frame is sized to 720x480. But the frame rate always
> >>comes out to 23.98. I ripped the files using Mac The Ripper 2.6.6.
> >>
> >>Any ideas what would cause this?
>
> I know nothing about Cinematize or DVDxDV, but I'll make an educated guess about what's going on:
>
> If an NTSC DVD was created from a 24 fps movie, it really only contains ~24 fps, along with a code that tells the DVD player to create one extra frame for each four given ones. (Presumably, the DVD player uses 3:2 pulldown to create the extra frames, but I don't suppose it has to!) When a program is converting the DVD's MPEG-2 file to a MOV (or AVI or MPEG-4) file for displaying the movie with a computer, there's really no reason to put in the extra frames, so the file is created with a frame rate of ~24 fps, as in the original movie. (I'm not sure why it would be at 23.976 fps rather than 24 fps, although 23.976 fps is exactly 4/5 of the NTSC frame rate of 29.97 fps.)
>
> (BTW, I'm curious why one would want to create a MOV file with a frame rate of ~30 fps if there really are only 24 frames per second in the original movie.)
>
> >DVDxDV and Cinematize both default to encoding at what is called "NTSC
> >Film" rate -- 23.976 fps.
>
> Do they do this even when the DVD was made from original NTSC video with ~30 original frames per second? I doubt it, and would have a low opinion of a program that did that, unless it were creating images to be put back on film!
>
> >If you check the frame rate of the VOB files
> >ripped by MtR, you'll see they're still at 29.97 fps.
>
> According to what indicator?
>
> >DVDxDV refers to
> >the as "3:2 Pulldown" -- you'll need to use DVDxDV Pro (or some other
> >converter) to avoid the pulldown implementation.
> >
> >--
> >Dennis R. Cohen
>
> If I'm right here, the program's that are creating the  23.98 fps MOV files ARE avoiding "the pulldown implementation", since they aren't creating any extra frames!
>
> BTW, I found a fairly good explanation of "3:2 Pulldown" at <http://www.dvdfile.com/news/special_report/production_a_z/3_2_pulldown.htm> and intend to reread it when I'm more wide awake. ;-)
>
>  - Aaron
>