Re: software for measurements from video images?

[Mark Sylvester <msylvest@spin.it>]

Many thanks for the comprehensive information - I'll check out all the options.

Ludwik, I've had students playback a video recording of a falling object
alongside a metre rule, using the frame-by-frame advance, to get position
measurements from the TV monitor. The measurements are crude, but the graphs
we got agree with your observation that there are noticeable fluctuations in
the timing between the frames recorded by the camcorder.

Mark.

> From: LUDWIK KOWALSKI <KOWALSKIL@alpha.montclair.edu>
>
> And I forgot to mention that I do not believe people who claimed that they
> get the free fall acceleration constnant (+ or - 5%) from the frames of a
> common camcorder. The average value, yes, but not consecutive five or more
> points based on local dx and dt. I could not eliminate fluctuations. please

*************************************************************
Mark Sylvester
United World College of the Adriatic, Duino, Trieste, Italy.
msylvest@spin.it
tel: +39 40 3739 255
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