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Re: Focal Lengtht




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>
>Questions: How is focal length calculated?
>

Greg Guffey
>---------------------------------------------------------------------------
Dr.Dish:


f =   r x r
     ----------
     4 x c

F= focal length
r= radius of the dish
c= depth of the dish

Example:
If you have a 150cm dish with a depth of 20cm, then it looks like this:


      75 x 75
f =   ----------  = 72.2cm
       4 x 20

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Christian Mass (Dr.Dish)
Editor of TELE-satellite International (http://www.TELE-satellite.com)
Producer of drdish@tv, Europe´s first satellite info-channel
(http://www.drdish.com)



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