Astronomy and observational optics · Astronomy tools

Telescope magnification

Estimate angular magnification from telescope objective and eyepiece focal lengths.

Published · R0

Method and scope

Magnification = telescope objective focal length ÷ eyepiece focal length; both lengths must use the same unit.

Calculate the paraxial angular magnification of a simple telescope and eyepiece combination. Intended for Learners, Amateur astronomy.

Inputs

SOURCE AND LIMITS

Assumptions: The entered focal lengths describe the objective and eyepiece used together. Focal lengths use the same length unit.

Limitations: Higher magnification does not guarantee a sharper or brighter image.

Method version 1.0.0 · Unit registry and result provenance are shown after calculation. This tool is limited to the documented scope.

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