The diameter of a telescopeโs main lens or mirror โ and the scopeโs most important attribute. As a rule of thumb, a telescopeโs maximum useful magnification is 50 times its aperture in inches (or twice its aperture in millimeters).
The diameter of a telescopeโs main lens or mirror โ and the scopeโs most important attribute. As a rule of thumb, a telescopeโs maximum useful magnification is 50 times its aperture in inches (or twice its aperture in millimeters).
