From: "Andrew Davidson" <andrew AT lemure DOT freeserve DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Allegro and dirty rectangles and fps
Date: Thu, 18 Feb 1999 05:04:51 -0000
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Ludvig Larsson <ludvig AT club-internet DOT fr> wrote in message
news:36CB8E75 DOT 3599 AT club-internet DOT fr...
>Ismael Herrera Zamarron(MCC) wrote:
<snip>
>Well, you need about 24 fps to get something good enough to fool
>the brain, Film at cinema has a 24fps and Most european TV 25fps(IIRC).
>After that, the bigger the better, with one condition, that is that the
>out unit (your screen) can be able to show these higher frame rates
>(most computer monitors has an update frequency of 60-80hz).
>Everything also depends on what to show, a not so much moving video is
>OK on 24fps, but a high speed F1 game could really benefice of 60.

Right, this is totally off-topic but it's something that's always flumoxed
me and I'd love a (preferably non-technical) answer. If cinema film is
recorded at 24fps and tv is recorded at 25fps to tv how come we can watch
films on tv without an at least slightly noticable judder as the final frame
in every second is repeated?
a 25th of a second isn't really noticable you say? Then what about film
recorded for ntsc tv and then played on pal tv. There's a 5fps difference
there and yet no judder. Now you can't tell me any cinema film is recorded
with a camera lens connected to three seperate reels of film, one at
24fps(film), one at 25fps(pal), and one at 30fps(ntsc) so what are they
doing?

Andrew