Guyot Leon wrote:
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On Date: Fri, 29 May 1998 19:33:55 -0400
Sam Gentry <hsgentry@cfw.com>
wrote Subject: Re: C&SC Video
NTSC is the US standard, PAL is European. It is the format of the video
information on the tape, not the physical format of the cassette. If you
are in the US you want NTSC.
Sam
According to my friend at the BBC, (tongue in cheek)...
NTSC, (the North American standard) means "Never Twice the Same Color"
PAL, (the British & Commonwealth countries standard) means "Pictures At
Last"
and there is also a French standard called SECAM, but I can't recall the
funny
meaning, or even the real meaning of SECAM...
We are advised that PAL videos won't work properly on SECAM video machines,
and you will get the sound, but the pictures will only appear in black &
white, which I have found, in practice, to be nonsense.
If anyone is wondering why we have all these different standards, it's
partly
to do with the U.S. TV running at a slightly different 'frequency' I think
?
(60 MHz instead of 50MHz? or something like that ? correct me if I'm wrong)
also, it is something to do with the big international media companies
releasing films at different dates around the world, depending on which
marketing zone you are living in...all to get as much money out of us mere
mortals as possible.
However, now we can get dual band video recorders/players switchable
between
NTSC and PAL.
Leon F Guyot
(just trying to make some sense of it all)
Joking aside, U.S.A. uses NTSC only.
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Very close, Leon. The folks on the east side of the Atlantic use
the PAL standard which uses a 50 Hz vertical refresh rate and we-uns
on this side use NTSC which has a 60 Hz vertical refresh rate. These
respective refresh rates were chosen to minimize interference from
the power mains which are what? 50Hz in Europe and 60 Hz in North
America, of course. In addition there are 525 lines in the NTSC
standard and 625 lines in the PAL. The picture is painted using
horizontal lines, left to right at a rate of 15 KHz which is just
above the limits of human hearing. The vertical refresh rate indicates
that the the picture is painted with horizontal lines 50 (or 60) times
a second. Interference from the mains power could cause a "flicker"
so setting the refresh rate equal to the mains frequency eliminates
this.
And now for something completely different. Why are there more than
one mains frequency? That is a topic for another time.
Dave (I took a course on that once) Massey
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