Re: software for measurements from video images?

[Leigh Palmer <palmer@sfu.ca>]

> Ludwig wrote:
> > . . .  The sutter speed was 1/1000.
> > Ludwik
>
> Each TV line takes roughly 50 microseconds,  each field about 8 ms and
> each frame about 16 ms.  Furthermore the two fields which make up a frame
> may be interlaced.  Given this, how does one interpret data taken
> with a shutter speed of 1/1000 sec (1 ms)?

If one can judge by the product, the image is frozen on the CCD in a
millisecond. That's whey they call it a "shutter speed". Of course
it is transmitted in a thirtieth of a scond (approximately), and it
is *always* interlaced in NTSC TV. Examination of the single frame,
however, will show the spokes of wheels as straight lines at 1/1000
shutter speed. That would not be the case if the particular
millisecond corresponding to the pixel being transmitted was the one
of interest. In that case the spokes would be curved and some might
even be missing.

Leigh