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2 Star alignment

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#1 hamdul

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Posted 05 April 2013 - 03:46 PM

Hi Guys,
I'm curious as to what stars to use in a 2 star alignment. No, not the names of the stars but there location. Is it better to select 2 stars with an East/West position or a North/South location? Or doesn't it matter? :question:
Fred

#2 Arctic_Eddie

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Posted 05 April 2013 - 04:40 PM

One north and the other east or west depending on which side of the meridian you plan to view.

#3 Tel

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Posted 06 April 2013 - 04:36 AM

Arguably, Fred, this one's being doing the rounds in one guise or another for a few years now ! :idea:

http://www.ilanga.com/bestpair/

Best regards,
Tel

#4 Bob Griffiths

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Posted 06 April 2013 - 11:25 AM

I used best pair for a long time...not a problems...

TODAY I always pick Polaris and then one close to 90 degrees apart in ANY DIRECTION...

BUT I do not choose that second star IF it is OVER 75 degrees above the horizon .... NOR lower then 30 degrees... (give or take lol)

Bob G

#5 Arctic_Eddie

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Posted 06 April 2013 - 12:18 PM

From a mathematical point of view, that's a good way of selecting a best pair.

#6 Arctic_Eddie

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Posted 06 April 2013 - 12:58 PM

Examination of the best pairs in the Tel's link show they are clustered around 90° separation. This is expected in an orthogonal coordinate system such as the AZ/AL mount.

#7 Skip

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Posted 07 April 2013 - 02:11 PM

Ditto Mr. Bob!






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