Posted by Steve on 12/26/06 14:50

I believe that in the case of that Mustek mp4 camera, the 3M pixel
resolution is only for stills. Video is captured using 640x480 of that 3M
pixels, period. Digital zooming uses a smaller and smaller portion of that
640x480. No camera regardless of price uses more than 720x480 to capture
digital video of any sort, anywhere. It's all the resolution one needs to
get the most out of NTSC TVs. If I am incorrect here, someone please jump
in!

As a test, go to a store where you can try out a camera with a long digital
zoom (like 300 to 1 or something) and zoom all the way in. You will find
you are looking at an image that's about 20 pixels wide!

Steve

"Jan Panteltje" <pNaonStpealmtje@yahoo.com> wrote in message
news:emonas$m9f$1@aioe.org...
> On a sunny day (Mon, 25 Dec 2006 05:20:24 -0800) it happened "Richard
> Crowley"
> <rcrowley@xpr7t.net> wrote in <12ovk0ro9e4dr7c@corp.supernews.com>:
>
>>"Brian Huether" < wrote ...
>>
>>> Most instructional videos I have seen show a waste up shot that shows
>>> enough detail of the player going through the exercises.
>>
>>And how effective is that? At that distance your fingers are
>>only a few pixels high. I wouldn't find that very helpful.
>>Might as well distribut an audio CD and some nice printed
>>close-ups.
>>
>>>Then again I haven't seen many recently. I would only do the digital
>>>zoom if there was enough resolution (i.e. if a normal DVD is 600x800
>>>(just as an example) and the camera is capturing 1200x1600 then I would
>>>feel pretty good about zooming).
>>
>>Video resolution is frozen at 720x480. This is the same
>>for every video camera in NTSC-land (720x586 in the
>>PAL-territories).
>
> Richard, I have a cheap Mustek mpeg4 one, that records on SD card,
> and I just tested that.
> It does 640x480 @ 30fps (or 25fps), and has digital zoom.
> The sensor itself is 3M pixels (2048 x 1536).
> For the same lens setting, and all digital zoom settings, the image
> is always calculated down to 640x480.
> This means if I zoom in digitally, then I will indeed pass a point
> where I am using only a 640 pixels wide part of the sensor :-)
> Digital zoom simply uses only a smaller area of the image sensor,
> and recalculates it to required the output format.

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