Aperture

Used telescopes up to 4 inches

Telescopes up to 4 inches (about 100 mm) across are the grab-and-go scopes. They're light enough to carry out in one trip and set up in minutes, and most are refractors. A good small refractor gives sharp views of the Moon, planets, double stars and bright clusters, and the premium ones are favorites for wide-field photography. They gather less light than bigger scopes, so faint galaxies stay faint. Used, they ship easily and the optics are simple to check.

10 models we cover.