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astronobob
25-04-2016, 11:28 AM
Just another weird 'Thunkin' thought ;)

When firing up my/the/your Neq6p or other mount, as most know with most mounts, I presume, it ask's for your time zone, which here Goldcoast/Eastern Aus in +10 hrs, Ok !
So, prior in the 'start-up' procedure, we inject the Lat/Long data, & go to lengths to have these values rather accurate, ie, GPS locations can be accurate to within 10mtrs for argument sake, ok, then We inject the Date & Time to the Minute, right !

Well, Iv'e always thunk - How accurate 'Eastern Aus' is the input of entering the +10hr - when realistically as the Earth rotates, through the timezones, the +10hrs at that instant of time is actually some several hundred kilometers off the east coast, here in SE QLD for this example !

So, theoretically, and roughly, going by the attached image, would it be not wise to say, I would need to wait some 15-20 or so minutes for that +10hr timeline to be, say, overhead or on the Gold Coast ? ?

Hence, when entering the time into the mount - would it be advantageous to take off 15-20 minutes, or for better understanding, set the time 15-20 minutes prior to actual current time of start-up in an attempt to better set the mounts parameters :question:
Therefore, may find the initial 1st star alignment and subsequent star alignments more accurately and in turn, the mount be more accurate ??

Further discussion and/or input could be interesting :question:

Camelopardalis
25-04-2016, 11:44 AM
Bob, it's just using the +10 and the local time you input to calculate UT.

ZeroID
25-04-2016, 01:07 PM
The Lat\Long data takes care of all that ..the clock is just the local reference zone.

astronobob
25-04-2016, 02:24 PM
:rolleyes: :rofl:
Thanx Dunk & Brent, I went off on a most misdirectional tangent on this one then, Lol :thanx:

JimsShed
25-04-2016, 08:15 PM
This was a great question because yes, time zones are a generalised measure. Bob you are correct that when looking up into the sky at say 8pm from the fabulous Gold Coast, that the position of the stars from your viewpoint are in fact different to those viewed by someone way out west but in the same time zone. As Brent succinctly states, the coordinates combined with the date/time/Timezone allow the computer to calculate an exact location for sky tracking where the mount stands.

astronobob
26-04-2016, 10:45 PM
Thanx Jim :thumbsup:

So now I understand with all replies, that for mount to distinguish where exactly on earth longitude it stands, the onboard interface controller has been programmed with each timezone around the earth, which then with the current time can zero in and pinpoint the longitude and/or UT 'Universal Time'
Makes sense now !
I thought that was all sorted when/why it always asked the time in 24hrs, , but no, thats irrelevant to longitudinal specification and/or Times zones, hence UT
Learnt something :thumbsup:
Rgrds all