On Tue, 08 Jan 2002 20:26:54 GMT, "Harry Johnson"
>Do they all have the same resolution after downloading to pc? Or those with
>higher ccd resolutions give bigger images?
>I'd like to know the number in pixels per frame such as 1024x768 for pc
>viewing.
>
>I also read about horizontal line resolution. Does this apply only to tv
>viewing, and if so, do different minidv cameras give different res for tv
>viewing mode?
>Thanks.
Welcome to the world of TV-resolution-confusion...! ;-)
The Mini-DV video format, unlike analogue, where increasing
the bandwidth (or pulling tricks) can increase format
resolution a bit, Mini-DV has a built-in resolution limit
of about 540 vertical TV-resolution lines (run in the
horizontal direction - the horizontal lines run in
the vertical direction is determined by the number of
scan lines, different for PAL and NTSC). Since this is
the format limit, and part of a resolution system, even
with the sharpest lens at its optimum stop, shooting
high-contrast subject material, with the best possible
CCDs and associated electronics, 540-line TV-resolution
can only be approached in Mini-DV, but not reached; with
lesser associated parts, figures as low as 350 lines may
be the maximum TV-resolution. Whatever the actual TV
resolution, though, it is "written" to 720x480 pixels
(NTSC), which are not square in order to permit higher
horizontal-direction resolution within the TV 4:3
aspect ratio - so the computer-viewed image will be
stretched horizontally a bit compared with the TV image.
Also, TV images are interlaced, so normal-mode shooting
of motion will be more sharply rendered on a TV than on
a computer monitor (which displays in the "TV-incorrect"
progressive-scan mode...). When the computer image is
converted back for TV-viewing, the pixel-resolution
becomes bandwidth again (which varies with the
original sharpness, and is not determined by [but is
limited by], the pixel resolution) - and sharpness can
also vary depending on the quality of the viewing gear...
Simple, huh? ;-)