Anyone have any ideas? With my webcam taking photos every 12 seconds I'd like
to calculate the probability of catching a flash of lightning in the
thunderstorms which must be heading our way soon.

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That'a a coincidence,i was just reading about that!
http://www.lightningtrigger.com/
Simon

On 03 Aug 2003 14:52:05 GMT, (SSpiers) wrote:

That'a a coincidence,i was just reading about that!
http://www.lightningtrigger.com/
Simon

A quarter of a second.

Ah.

48-1 chance of my webcam capturing a strike... I guess I can bump up the
capture framerate on demand...

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| Nick Humphries |
| The Your Sinclair Rock'n'Roll Years: http://www.ysrnry.co.uk/ |
| The YSRnRY TV Show (Coming Soon) http://www.ysrnry.co.uk/tvprog/ |
| The Tipshop: http://www.the-tipshop.co.uk/ |
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On Sun, 03 Aug 2003 16:55:22 GMT, Pieter Kuiper wrote:

Maybe one can do something with motion detection software.

But by the time it's been detected it's probably finished...

A single flash is going to be substantially less than a single frame
in duration a whole strike (ie a sequence of flashes) may well take
the 6 frames or so that occupy 1/4s. You need to be able to compare
adjacent frames in pretty much the frame blanking period which isn't
very long if you going to stand any chance.

Other problems I can envisage are exposure and electronic shutters.
Lighting is very bright, unless you can set the exposure of the webcam
I'd expect no much better than a peak white frame. An electronic
shutter may mean that an image is only caputured for a very short
period of time around 1/500 to 1/1000s so the cahnces of teh shutter
actually being open when a flash occurs become even slimmer.
Electronic shutters are some times used as a easy form of automatic
exposure control.

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Cheers
Dave. pam is missing e-mail