Astronomy TrainingUsing a Telescope:There are two basic types of mounts, either Equatorial (of one type or another) or simple, Alt/Azimuth mountings. The latter is much simpler and much more geared toward visual users than those of us that use the equipment for imaging. In an Alt/Azimuth type setup you can typically move the telescope around the sky at will. The scope is not aligned toward the Celestial Pole, so if you were to take pictures through it they would suffer from field rotation. In an Equatorial mount that is not the case. One axis of the mount is aimed toward the North Celestial Pole (for us Northern Hemisphere Users, anyway) and as the telescope tracks an object, the only drive it really uses is Right Ascension. The Dec Axis is pointed toward the pole, and the RA axis simply follows the object it's trained upon, around the pole. This is easy to picture, but not as simple as it sounds.
The adjustments to the mount for proper Polar Alignment are precise and must be done exactly for star drift to be eliminated. The types of adjustments depend upon the type of mount you have; there are different Equatorial type mounts out there. SCT telescopes typically are sold on a Fork Mount. Mounted flat on it's tripod, this mount is an Alt/AZ type. When installed on a wedge however all of a sudden you have an fine EQ mount that requires the Polar Alignment Process to work correctly. Many volumes have been written on this process and it will be the subject of a different article in this website. --- --- ---
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