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Old 15-01-2014, 02:29 PM
AndrewJ
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AndrewJ is offline
 
Join Date: Mar 2006
Location: Melbourne
Posts: 1,905
Gday Baz

Quote:
I should have said gets where the scope is pointing after alignment or intermediate positions when slewing to a new position.
Yep, but as i noted, i was just being pedantic ,
as the two commands can give very different results.

Also, just as another aside, based on yr clarification above,
reading RA/DEC "during slewing" is even more fraught with error,
as Meade uses another set of different "faked" variables to report the RA/DEC based on "projected" positions in time.
Ie in AltAz for final tracking, they calculate a point a set period in time ahead of now, and set the Az and Alt motor rates accordingly, ie they adjust the motor speeds until current matches projected. This mechanism allows any residual error, backlash etc to be accounted for,
but can create other problems ( like DEC guiding in polar with the latest Audiostar firmware )
Until the slew is almost finished, these projections wont be stable, but they may also not relate to reality, so again, a grain of salt is reqd if the data is to be "relied upon".

Andrew
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