An Altazimuth or alt-azimuth mount is a simple mount used for moving a telescope or camera along two perpendicular axes of motion. The vertical movement is known as the altitude, while the horizontal motion is called the azimuth. Mount can mean: a horse or other animal or bird intended for riding; for example, a horse, camel, elephant, or Garuda an attachment point for equipment to vehicles, usually made to enable the object mounted there to be moved in relation to the vehicle, but still remain affixed. ... 50 cm refracting telescope at Nice Observatory. ... A camera is a device used to take pictures (usually photographs), either singly or in sequence, with or without sound, such as with video cameras. ... Perpendicular is a geometric term that may be used as a noun or adjective. ... A coordinate axis is one of a set of vectors that defines a coordinate system. ... Altitude is the elevation of an object from a known level or datum, called zero level. ... Azimuth is the horizontal component of a direction (compass direction), measured around the horizon from the North point, toward the East, i. ...

The biggest advantage of alt-azimuth mounts is their simplicity in both manufacture and use. They are often used for beginner telescopes, or for spotting scopes, but are still widely in use for more advanced telescopes. In the latter case, advanced electronics and motors are sometimes attached to compensate for the restrictions of the mount's simplicity.

In astronomy, alt-azimuth mounts were, for a time, surpassed in popularity by the more complex equatorial mount. The latter is more naturally suited for tracking astronomical objects in the night sky as the Earth spins on its axis, since its polar alignment means that only one axis need be adjusted rather than the two of an alt-azimuth mount. Being able to track such objects reliably is particularly important for astrophotography, as well as more advanced amateur astronomy, both of which became more accessible when equatorial mounts became affordable. In ancient Greece and other early civilizations, astronomy consisted largely of astrometry, measuring positions of stars and planets in the sky. ... An Equatorial Mount for a telescope. ... See lists of astronomical objects for a list of the various lists of astronomical objects in Wikipedia. ... Amateur astronomy, often called back yard astronomy, is a hobby whose participants enjoy observing celestial objects. ... Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third planet outward from the Sun. ... Astrophotography is a specialised type of photography that entails taking photographs of items in the night sky such as planets, stars, and deep sky objects. ... Amateur astronomy, often called back yard astronomy, is a hobby whose participants enjoy observing celestial objects. ...

In recent decades, alt-azimuth mounts have once again become very popular for astronomical telescopes:

• The Dobsonian mount—a variant of the alt-azimuth mount—has become very popular since about the 1960's. This is due to its ease of construction. Although it is difficult to attach an automated drive system to a dobsonian mounted telescope, it has become very popular for its suitability for very large amateur telescopes that cannot be conveniently mounted on an equatorial mount.
• Affordability of modern electronics has been a further motivation for a return to alt-azimuth mounted telescopes, with their increased simplicity for manufacture and practical use. In particular, it has often proved more convenient to build a simple alt-azimuth mount and use a computer to manipulate both axes to track an object, than to build a more mechanically complex equatorial mount that employs only a single motor. When astrophotography is involved, a further motor may be used to rotate the camera to match the field of view.

In astronomy the Dobsonian is a type of telescope mounting that became popular in the 1980s for its extreme simplicity, low price, and rugged construction. ... A computer is a device or machine for making calculations or controlling operations that are expressible in numerical or logical terms. ...

See Also

• Telescope
• Telescope mount
• Equatorial mount