Telescope eyepieces. Understanding focal lengths

To work out the magnification of any given eyepiece on a telescope, simply divide the focal length of the telescope by the focal length of the eyepiece.

For example a telescope with a FL of 1000mm with a 10mm eyepiece (1000 divided by 10) will give 100x magnification. So a 5mm will give 200x. If unsure, ask the dealer who will help explain.

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