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Help with a compass

Started by SmokeDaddy, 04/28/2007 05:43PM
Posted 04/28/2007 05:43PM Opening Post
Sure would apprecaite some speific help with reading a compass I picked up today at a neighbors yard sale. I have the manual, and yes, I did read it but still confused. I set the magnetic declination as per the manual for my area 11,27 East. Here are my specific questions if you can help.

I purchased it so I can setup my mount in the daytime better, as I don't have a fixed pier.

1. Regardless what compass I am using, am I looking for magnitic North or True North?

2. On my specific compass, the blue graduation dial, the one with the blue circle is for compass bearings (forward/back). In the image below, I have it set at 0 degrees. The red (N) is the magnetic north arrow. How do I set my mount up accurately with a compass like the one below. BTW, I have asked Brunton Compass but they weren't any help.

http://www.pbase.com/smokedaddy/image/77868510

Thanks in advance,
-JW:

Posted 04/28/2007 08:33PM #1
Hi James,
http://www.compassdude.com/compass-declination.shtml
Check this link

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Posted 04/29/2007 03:25PM #2
So what do you think,

Thanks for all the help, links and suggestions. Please don’t take this wrong and I do appreciate the help. I understand where to find my magnetic declination for my area, as I listed it in my original posting, and HOW to configure the compass for that. I just don’t know how to use the compass to setup my mount. I realize it won’t be perfect and only close.

So, the compass is setup and configured for my magnetic declination. When I set it to 0 degree’s bearing (as shown in the image below, green numbers), the red magnetic arrow point to magnetic North. If I move the green dial to my magnetic declination of 11 degrees, I would assume that would be true North? I could then sight my telescope in via the white marks on the compass (called a forward bearing)? Make sense?





Attached Image:

SmokeDaddy's attachment for post 113630
Posted 04/29/2007 03:36PM | Edited 04/29/2007 03:39PM #3
... last image promise ...

This looks correct to me. The compass is pre-set (internally, not the green numbers) by me for my declination in my area. This corrects for the declination. If I want to forward shoot a bearing for my mount, then I set the green dial to 11 degrees, then line up the 2 white lines with the blue one?



Attached Image:

SmokeDaddy's attachment for post 113631