<<Alternatively, you can simply move the mic in and out on its mount and
listen to the signal the mic produces to find the spot where you get
the best results.>>>
I have been recording with parabolic dishes for over 30 years and this is
the only way to do it in my opinion. You determine the "sweet spot", forget
about the measurements and when you find it, you will intuitively find it
every time you set up to record.
Martyn
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Martyn Stewart
Bird and Animal Sounds Digitally Recorded at:
<http://www.naturesound.org/> http://www.naturesound.org
Redmond. Washington. USA
N47.65543 W121.98428
e-mail:
Tel: 425-898-0462
Make every Garden a wildlife Habitat!
*****************************************
_____
From:
On Behalf Of oryoki2000
Sent: Friday, September 29, 2006 6:32 PM
To:
Subject: [Nature Recordists] Re: DIY Parabolic Dishes.
"John Hartog" wrote:
> Would the optimal position of the focus be at a certain
> ratio of the dish depth?
I like this approach:
"...Rather than trying to make measurements to determine the equation
and calculate the focus from those measurements, you'd be better off
finding the focus directly by experimentation.
[Assuming the parabolic dish has a reflective surface] Shine several
parallel light beams at the dish, each parallel to the main axis of
the dish, and observe where they converge.
You'd likely get more accurate results that way than trying to
determine the equation of the dish by measurements."
http://www.math.
<http://www.math.toronto.edu/mathnet/questionCorner/parabolic.html>
toronto.edu/mathnet/questionCorner/parabolic.html
Alternatively, you can simply move the mic in and out on its mount and
listen to the signal the mic produces to find the spot where you get
the best results.
--oryoki
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