From: Paul J Collins (sneakums at domain zork.net)
Date: Tue 01 May 2001 - 11:37:37 IST
>>>>> "JW" == Jerry Walsh <jerry at domain aardvark.ie> writes:
JW> It's half that? you're saying its 25hz and 50hz when
JW> interlaced? Hertz and frames aren't the same thing - Hertz is
JW> per second, so if you get a half a frame 25 times per second
JW> then you're ending up with 12.5 frames a second.
PAL is inherently interlaced. You get 50 fields per second. Each
successive field has the odd lines and the even lines. Hence, 25
frames per second. Each frame has 625 lines, IIRC.
NTSC, used in the United States and some copycats thereof, uses 60
fields per second, yielding 30 frames per second. Interlaced again.
NTSC frames have 525 lines or thereabouts.
Neither was good enough for the Fench, who prefer weak cryptography
and a TV system called SECAM.
-- ///////////////// | | The spark of a pin <sneakums at domain zork.net> | left blank. | dropping, falling feather-like. \\\\\\\\\\\\\\\\\ | | There is too much noise.
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