On 30 Aug 2000 17:27:23 GMT, lawrence@vex.net (Lawrence Kwan) wrote:

>If you look at the specs I quoted carefully, you will know that you are
>not correct.
>
>Both TRV20 and TRV520 use 1/4" CCD.
>
>TRV520 has 460k total pixels, of which 290k are "effective pixels" (actual
>pixels for the video frame, the rest of the pixels are for electronic
>image stabilization). This means that 290k/460k or 63% of the 1/4" area
>is for light capture for the video frame.
>
>TRV20 has 1,070,000 total pixels; 1,000,000 can be used for digital
>stills, while 690,000 pixels are "effective pixels" for video. This means
>that 690/1070 or 64.5% of the 1/4" area can be used for light capture for
>the actual video frame. So if anything, TRV20 has a slightly *larger*
>light sensing image area for the video frame; the difference is probably
>insignificant.

This is true if 690k pixels are used for the video image,
and a larger number is used to accommodate DIS - but the
Sony specs are not clear on this (Sony tends to obscure
such info as whether or not DIS or OIS is used in some
camcorders, and I would not be surprised if Sony is
being obscure here, too - especially if one looks at the
CCD specs for the PC-1/5...;-).

>Hence, any difference in low light sensitivity between the two camcorders
>is not due to the difference in light capture area; it probably is related
>to the difference in CCD and optics design.

I doubt it on the optics, but agree with you on the
CCD... BTW, it is not the CCD area, but the pixel size
(and CCD type) that is important for sensitivity
(of course, for a given size, more pixels means
each is smaller...;-). Some cameras use "pixel-offset"
to reduce pixel count (and increase size) while maintaining
image resolution - but this generally has some negative
effects on image quality.