🚀 go-pugleaf

In article <1992Dec19.225450.21560@cs.uoregon.edu> mkelly@mystix.cs.uoregon.edu (Michael A. Kelly) writes:
>In article <1992Dec19.221442.3741@news2.cis.umn.edu> toddl@county.lmt.mn.org (Todd Lehman) writes:
>>It's the same kind of effect you
>>see when 24 f.p.s. movies are converted to 30 f.p.s. video cassette format
>>by doubling up every 5th frame.  (Ever wonder why movies on TV look kind-of
>>jerky, but live video such as talk shows and soaps look smooth?)
>
>I've never noticed this effect.  Are you sure it isn't just you? :)

Pretty sure.  As a child I had always wondered why live video (e.g. local
news, sit-coms, SNL, Letterman) looked so smooth, yet things like movies and
a lot of prime-time television shows looked jerky.  One day I sat down and
freeze-framed Star Wars after taping it on network TV.  The frames repeated,
like this:

    1 2 3 4 5 5 6 7 8 9 10 10 11 12 13 14 15 15 16 17 18 19 20 20 21 22 ...

That must be how they convert a 24 f.p.s. movie to 30 f.p.s. video.  Pretty
gross, huh?

I also then freeze-framed a video version of some old Whinnie the Pooh
cartoons (with my little sister's premission of course), and apparently
there they had carefully interpolated the images for a smoother effect.

I don't know if they routinely interpolate images nowadays when converting
movies to video, but my hunch is that they don't, since they still look
pretty jerky.

The most noticible demonstration of this conversion effect is a prime-time
sit-com that normally films in video indoors.  If they step outside for a
few minutes, they may choose to use movie cameras for better lighting, and
you'll notice the difference in smoothness.  It's pretty subtle if you don't
know what to look for, but you'll notice that something is different.

I wish I knew more about this subject (I only know what I have observed and
deduced, and it all may be quite wrong) because it's all pretty wild to me.

--
Todd Lehman
toddl@county.lmt.mn.org