RE: [APML]: Great RA Alignment tool

[Ben Gomes-Casseres <ben@alliancerevolution.com>]

Wil, what is the difference between *variation* and *deviation* in this 
context? In Curacao, I set my adjustable compass to point 7 degrees to the 
west of true north, as my marine map shows that as the local magnetic 
"variation." I hope that's right...but what is deviation then?

Ben

-----Original Message-----
From:   Wil Milan [SMTP:wmilan@airdigital.com]
Sent:   Sunday, February 08, 1998 1:18 PM
To:     astro-photo@nightsky.com
Subject:        Re: [APML]: Great RA Alignment tool

I couldn't figure out how a
compass could be preset for magnetic variation, considering that in some
parts of the world you don't have to drive very far to have a significant
change in magnetic variation (which is not the same as magnetic
*deviation*, a different effect altogether).

Wil M.