A set of encoders on the axes of an unmotorised telescope, often a Dobsonian, linked to a handset or phone. The screen shows which way to push the tube to reach the chosen object. You keep the simplicity of a manual mount, with help to find things.
Related terms
- GoTo
A motorised, computer-controlled mount that slews by itself to objects chosen from its database, then tracks them. After switching on, you align it on two or three bright stars. It saves time, but learning the sky still helps when it gets lost.
- Dobsonian
A Newtonian telescope on a simple box base that swings up and down and turns round, popularised by John Dobson in the 1960s and 1970s. You nudge it by hand to follow objects. Quick to set up and very steady, it gives a beginner the largest aperture.
- Setting circles
Graduated dials on the axes of an equatorial mount, in right ascension and declination. Once the mount is polar aligned and set on a known star, you dial in an object’s coordinates to find it. The digital encoders of push-to systems are their modern version.
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