Optical Telescopes The telescope is a device that permits distant and faint objects to be viewed as if they were much brighter and closer to the observer. Most telescopes work by collecting and magnifying visible light that is given off by stars or reflected from the surface of planets. Such instruments are called optical telescopes. Optical telescopes use a curved lens or mirror to collect light and bring it to a focus. A small magnifying …showed first 75 words of 520 total…

…showed last 75 words of 520 total…fraction of the time required for a smaller telescope. Larger reflecting telescopes can typically detect objects that are a millionth or a billionth the brightness of the faintest star seen by the human eye. The Schmidt Telescope The Schmidt camera telescope is a catadioptric system used for wide-angle photography of star fields. The primary mirror is spherical instead of parabolic , which requires that a special correcting lens be used on the front of the tube.