How does EQ goto mount alignment work?
I've just bought a Celestron AVX goto mount, but don't yet have a telescope, so haven't been able to try it out fully. I have some basic questions about how the setup and alignment process works.
1) If the mount is only very roughly polar-aligned (i.e. just setting latitude scale and moving tripod to point roughly to pole - South in my case), what function does the "one star" or "two star" alignment have if it doesn't physically change the mount position?
It seems to me that this may allow the mount to become aware of it's orientation, and maybe calibrate its go-to ability, but wouldn't fundamentally allow it to track objects because the polar alignment is not accurate. Does the mount do some adjustment to compensate for poor tracking by using both RA and Dec motors, in the way that I imagine Alt-Az go-to mounts work (which I assume must use both motors as they are not polar aligned at all)?
2) it makes sense that the mount must be physically aligned to the celestial pole by moving its altitude and azimuth settings, but the manual is pretty bad in explaining this. I gather that the physical alignment can be done by centring a known star multiple times and offsetting drift according to direction prompts on the hand controller. When the drift is zero over time, then the mount is correctly aligned. Is this how it works?
I haven't been able to experiment with the above without a scope, so any clarification you could give would save me time when I actually get the scope!
Thanks and best regards,
John.
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