Posted by kim on 12/12/06 20:30

"Justin Cole" <jus.coleNO@S-P-A-Mntlworld.com> wrote in message
news:rZDfh.5738$z01.5723@newsfe3-gui.ntli.net...
> "fwibbler" <thedoctor@thedeathzone.free-online.co.uk> wrote in message
> news:gemini.ja4tug0018mdf0204.thedoctor@thedeathzone.free-online.co.uk...
> > Hmmm, AIUI,
> >
> > Film is shot at 24 frames per second.
> > NTSC works by slowing this to 23.976fps and taking every 4th frame and
> > duplicating it. So for every 4 frames of footage, 5 frames get
displayed.
> > this brings the frame rate up to 29.97fps.
> >
> > This tends to lead to motion judder (not sure if that is the official
term
> > for it)
>
> It's a little more complicated than that. Whole frames (2 interlaced
fields
> per frame) aren't duplicated, 3:2 pulldown is used where some fields are
> shown for slightly longer than others. This does introduced a slight
judder
> on horizontal panning especially. Some people notice it others don't.
>
> However, 3:2 pulldown removal on a non-interlaced display can almost fully
> remove the problem.

No it doesn't. The 2:3 pulldown sequence is added back in after the
deinterlacing.

(kim)

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