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Re: (meteorobs) polar alignment



Title: Re: (meteorobs) polar alignment
on 11/11/01 7:52 PM, Tom Scoot at t2scott@bellsouthdot net wrote:

This is not off-topic because I am putting  a new polar-alignment scope
on my barndoor tracker for Saturday night.
Can anyone tell me what the field of view of a 4X15 riflescope
is? Is that enough information?
TIA
Tom Scott
t2scott@bellsouthdot net



Tom, the easiest way to determine the field of view of your riflescope is to point it at something a few hundred feet away and measure the linear dimensions of the field of view. For example, you point it at a fence 200 feet away. Say the fenceposts are ten feet apart. Count how many fenceposts you can fit into the field of view -- that gives you the linear field of view. (Of course, in the real world, you'll probably have to measure both the range to the fence and the width of the measured field). Now divide the width by the range, and you get the number of radians in the field of view. Multiply by 57.3 degrees per radian, and you have the field of view in degrees.

This is really just an approximation, but it's almost certainly close enough for your needs.

Chris
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