Quote:
Originally Posted by gary
Hi,
Generic amateur mounts often come with one fixed rate and the best approach with these is to align with the refracted pole rather than the 'true' pole.
There is a different 'ideal' pole for every value of HA.
Again, the best compromise is to align with the refracted pole
above the 'true' pole and for most practical purposes you are likely to achieve
a useful outcome.
Best regards
Gary
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Hi,
I did some reading about the "King Rate" and was surprised at what I found as compensation for effects of refraction is not very commonly found in amateur guides, or maybe just the ones I used.
Is there any guide that correlates HA and the refracted pole.
how do we calculate the "offset from true north" to get the refracted pole if we know the Latitude?
when you say there is a different ideal pole for every HA, does this mean RA Axis alignment needs to be adjusted depending on HA?
Do Argo Navis or other automated systems use feedback from the Dec Axis to correct the tracking rate?
again, is there some sort of table or guide to calculate variance in sidereal rate for various points between horizon and zenith?
or is it just sufficient to point to the refracted pole to compensate.
I'm aiming for exposures between 15 and 30 minutes.
For DSO's with mag 12, would this exposure time be sufficient to capture nominal detail?