Rich field telescope

A rich field telescope (or large field telescope) describes a telescope with a short design with an aperture ratio from f / 6 and usually a wide-angle eyepiece . It is mainly used for deep sky observation in order to be able to see large-area objects ( groups of galaxies , nebulae , etc.) as a whole.

The closer the exit pupil corresponds to the pupil diameter of the dark-adapted eye (approx. 6-7 mm), the better the visual surface brightness . The disadvantage of a lower sharpness at high magnifications or incomplete color correction , which are particularly disturbing when observing objects in the solar system, can be accepted.

Both simple achromatic telescopes and powerful binoculars (e.g. 7x50) are suitable as rich field telescopes . The more commonly offered 10x50 binoculars or the earlier standard 8x30 glass are less suitable.

See also: Comet Finder