Mountings for astronomical telescopes come in various designs. These include alt-azimuth mounts, dobsonian mounts, german-equatorial mounts, and fork equatorial mounts. Regardless of the type, the mounting for the telescope should be sturdy enough to stabilize the telescope and hold it rigidly for viewing. Nothing is more frustrating than a good telescope on a poor mount that allows the telescope to vibrate and wiggle at the lightest touch. With such a mounting the image will never appear still enough for serious observing and the effort may as well be abandoned. Be wary of cheap, inadequate mountings.
I have observed with many different types of telescopes mounted on various mountings. Serious work can be performed with any type as long as it supports the telescope adequately. However, I strongly prefer equatorially mounted telescopes that are motor driven or other types that can be programmed to follow Earth's rotation. While an alt-azimuth, dobsonian, or hand driven equatorial mount can be moved by hand to place the object in the field of view, this is less than satisfactory. The continuous interaction with the telescope to keep up with the planet, especially when using high magnification, is tiring and consumes valuable observing time and hinders concentration. Equatorial mountings allow the telescope to rotate with the rotation of the earth and keep an object in the telescope field of view while moving around only one axis. The declination axis allows the telescope to move in the north-south direction, and the polar axis allows the telescope to move in the east-west direction. The polar axis is aligned with Earth's polar axis. The two main types of equatorial mountings are German-equatorial mountings (Fig. 7.7) and fork-equatorial mountings (Fig. 7.8). I also prefer mountings that are equipped with electronic slow motion controls so the planet can be easily centered in the field of view without touching the telescope by hand. Sometimes it is desirable to sweep the planet back and forth ever so slightly while viewing to help the eye detect subtle features. This sweeping is easily performed with no vibration transmitted to the telescope when using slow-motion controls. This technique is also effective for finding what I refer to as the "sweet spot" in the field of view. This varies with eyepiece and eye from observer to observer.
Mountings that are overbuilt are preferred over ones that are much too small. This may seem like an obvious statement, but heavier mounts perform much better
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