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Old 18-05-2010, 08:06 AM
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Satchmo
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Join Date: Dec 2005
Location: Sydney
Posts: 1,883
The 'apparent' angular size of the airy disc gets larger with increasing magnification. The physical size of the airy disc at the focal plane for a given f ratio is constant . The Airy disc has the same physical diameter at the focal plane in microns for example in a 0.1meter scope and a 10 meter, if the F ratio is the same.
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