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Old 28-05-2021, 12:40 PM
astro744
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astro744 is offline
 
Join Date: Apr 2007
Posts: 1,046
The idea of having an equatorial mount is so that once aligned with the south celestial pole one only needs to move the RA axis when tracking an object either by hand or motorised. You have a refractor so when looking at something in the north you have to decide if you want your tube to be east of the polar axis or west. I usually decide this such that the counterweights are not higher or going to be higher soon in time than the telescope in a horizontal plane (east-west).

Using a Newtonian reflector introduces problems with the way the eyepiece is pointing. It could be pointing down on one side of the polar axis and up on the other often neither at a convenient angle. My first telescope was (and still is) a 6" f5.5 Newtonian on a Vixen Polaris German Equatorial mount. I understood that the polar axis had to be aligned with the Earth's axis of rotation but all too often it was just more convenient shifting the mount laterally just so the eyepiece was at a convenient angle. If I wasn't worried about tracking then it simply meant using both RA and DEC slow motion knobs to re-center the object just like in Alt-Az. Comfortable viewing was more important than RA only tracking.

If wanting to track with a motor though you have no choice and for a Newtonian then a set of rotating rings is nice (often expensive). Refractors are easier on a fully aligned EQ. You just walk the OTA around the mount when switching from one side to the other (unlock both axis). I use a TV-101 on a GM8 and the best thing about the GM8 is that there are no axis locks so one simply tightens the clutches for a secure fit and then when one wants to change targets one simply moves the telescope around and it stays in the new position.

Last edited by astro744; 28-05-2021 at 05:06 PM. Reason: Corrected misleading typo.
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