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How does one determine magnification? I have an Edmund Scientific Astroscan, 4-1/8-inch aperture, F/4.2 reflecting telescope, used with a 2.5x Barlow lens and a 28mm Plossl eyepiece.

Pete Condon, Girard, Ohio
RELATED TOPICS: EYEPIECES
Orion
The magnification (or power) you will see through a given optical system depends on the telescope and the eyepiece.

The simple formula is: Magnification = Focal length of telescope ÷ focal length of eyepiece.

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