Telescopes are optical devices that observe distant objects through the emission, absorption, or modulation of electromagnetic radiation. These devices may use lenses, curved mirrors, or similar devices to magnify distant objects.

That light is what we see when we look through a tele. A tele is a tool used by astronomers to view distant objects. Most teles, and all large teles, work with curved mirrors to collect and focus light from the night sky. Early less focused light using curved pieces of glass called lenses.

Capture and resolution of light. The most important of all the powers of an optical tele is its light-gathering power. This power is a constant function of the objective diameter, that is, the aperture, of the tscope.

Most under $150 have poor optical quality and aren’t worth the price. We recommend getting good binoculars. Stay away from any advertised for its magnification. The most important aspect of a is its size, which is the diameter of its main mirror or lens.