Altazimuth mount

These mounts are used, for example, with telescopes, cameras, radio antennas, heliostat mirrors, solar panels, and guns and similar weapons.

The primary disadvantage is its inability to follow astronomical objects in the night sky as the Earth spins on its axis.

Altazimuth mounts need to be rotated about both axes at variable rates, achieved via microprocessor based two-axis drive systems, to track equatorial motion.

[1] On smaller telescopes an equatorial platform[2] is sometimes used to add a third "polar axis" to overcome these problems, providing an hour or more of motion in the direction of right ascension to allow for astronomical tracking.

When tracking at elevations close to 90°, the azimuth axis must rotate very quickly; if the altitude is exactly 90°, the speed is infinite.