Magnifying Power

The magnification of a telescope is the ratio of the focal length of the objective lens or mirror FO divided by the focal length of the eyepiece FE..

M = FO / FE

Example:   What is the magnification of a telescope whose focal length is 80cm used with an eyepiece whose focal length is 0.5cm?
Solution:  The magnification is 80 divided by 0.5, or 160 times.

Magnification Calculator by Matt Oltersdorf

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