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Old 04-02-2019, 04:49 PM
JA
.....

JA is offline
 
Join Date: Oct 2016
Location: Melbourne, Australia
Posts: 1,318
Quote:
Originally Posted by Pepper View Post
Yeah def pointing south...........ish
Did a little testing yestiddy while cooking tea, I let it run and monitored the axis movements. Dec didn’t budge, ra was tracking at 1 degree/4 min and seemed to be rotating the correct way.
I did notice however my altitude setting screws were a few deg out. So polar alignment was probably bad.
Would my symptoms describe bad polar alignment?
Yes, especially as you say you ...

Quote:
Originally Posted by Pepper View Post
need to up and right button to recenter.
That's not to say that there may not be other issues, but certainly a large error in polar alignment would have similar symptoms to what you reported. As to the apparent speed of the motion across your display, that would depend on your focal length and the angular distance the object is away from the South Celestial Pole.

To understand the abberant motion you mentioned think of two circles that need to be concentric around the South Celestial Pole: one describing the true star motion and the other the rotational axis of your mount. Now set these two circle centres askew vertically to try to recreate your altitude error and you can possibly see how this could lead to the abberant motion you observed. I think it's a good thought experiment.

Best
JA

Last edited by JA; 04-02-2019 at 05:01 PM.
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