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Correcting Lat and Long after 2+4 alignment

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Posted 12 September 2013 - 06:08 AM

I have recently found my precise Lat / Long co-ordinates and wish to override the original figs I keyed on the H/controller of my CGE PRO to improve my GOTO accuracy.

Am I correct in thinking that changing the lat/long after star alignment may require completing another 2+4 star alignment to benefit from the improved Lat /Long.
Would welcome any help. Thanks and clearskies.

#2 rmollise



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Posted 12 September 2013 - 07:20 AM

Latitude and longitude really only has one effect: It lets the scope know what is over the horizon. It will NOT improve go-to accuracy.

You do not need precision. Within 60-miles is more than good enough. I can't answer your question because I've never tried it and I have never heard anybody else ask it.

Don't worry about it, or if you can't help worrying about it, enter new position figures next time you use the scope before you align it.

#3 jrcrilly


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Posted 12 September 2013 - 07:22 AM

Prior to star alignment, the controller makes certain presumptions regarding the directions of celestial objects. It uses these presumptions to do initial alignment star slews. Star alignment is the process of replacing those presumptions with actual directional data. In general, whatever inaccuracies existed in that preliminary data are no longer relevant. They will have no effect at all, for example, on goto accuracy for non-solar system objects. The location info IS used to calculate solar system object motion relative to the stars as seen from the observer's location so goto operations to those objects will suffer is the location info is off by more than a degree or two.



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Posted 12 September 2013 - 08:03 AM

Many thanks for your advice, Uncle Rod.
Clear Skies

#5 MartinTreadgold


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Posted 12 September 2013 - 09:57 AM

I have the skysync GPS, its useful for not having to worry about the date-time-location... saves me a few minutes of fumbling around in the dark

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