Date: Tue Dec 18 15:17:37 2007

Author: Paul Nord

Subject: Re: High-Speed video of quarter lift

Post:
John,

It's the Troubleshooter 500 made by Fastec Imaging Corp. The camera
was about $9000 with the "accessory kit" which includes a lens, light,
tripod, and a case.

They also have a 1000 fps version for another $2k. I kinda wish we
had held out for the faster frame speed. The video I made of a hammer
hitting a nail, for example, only gets 3 frames during the contact
time at 500 fps. You can set a faster "shutter speed" so that the
motion does not blur. But six frames of hammer contact would have
been interesting to see and would make a more convincing measure of
the impulse.

This, as it turns out, is the low-end of the high-speed camera world.
It's black and white and only a few hundred frames per second. If you
have tens of thousands to spend, there are some really cool things in
color. Of course, with color, you will need more light.

Paul

On Dec 18, 2007, at 1:58 PM, John Welch wrote:

> Great video Paul - it's going to reopen a debate we've been having
> here about that demo.
> Can you tell me what the camera was that you used, and roughly how
> much one costs?
> -John
>
>
> Paul Nord wrote:
>> Good Day,
>>
>> I'm having great fun with my high-speed video camera.
>> http://www.youtube.com/watch?v=fC8q4S4t8Ts
>>
>> This is the demonstration where you blow across top of a quarter
>> and cause it to lift up off a tabletop and fling itself into a
>> cup. And, just to get people talking, I've titled the youtube
>> release "Bernoulli's Principle". If you watch this frame-by-frame
>> you can see that the quarter lifts straight up about 1/8" and then
>> tips forward then backward before getting caught up in the air
>> stream.
>>
>> It's a really startling demo to see in person. Just amazing in
>> slow motion. Captured at 500 frames per second. Played back at 30
>> fps. Except for the third run through where it's played back
>> slower. (I don't know how slow, it's just iMovie.)
>>
>> Paul
>>
>>
>
> --
> ******************************
> John Welch
>
> Cabrillo College Physics Dept.
>



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