ATRONOMY – TELECOPE & OPTIC (46) CALCULATOR
Magnification Calculator
A precise tool.
What is the Magnification Calculator & How does it work?
Magnification tells you how many times larger an object appears through a telescope compared to the naked eye. It is a fundamental concept for selecting the right eyepiece to achieve the desired view of planets, nebulae, or deep‑sky objects. The calculation is based on the ratio of the telescope’s focal length to the eyepiece’s focal length. A longer telescope focal length or a shorter eyepiece focal length yields higher magnification, but practical limits exist due to atmospheric seeing and optical quality. Understanding magnification helps astronomers balance field of view, brightness, and resolution. Using the formula below, you can quickly determine the magnification for any combination of telescope and eyepiece.
M = \\frac{F_{tel}}{F_{eye}}
M = magnification, F_{tel} = telescope focal length (mm), F_{eye} = eyepiece focal length (mm)
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Result
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Results are for informational purposes only and do not constitute professional advice.