METHODS FOR POLAR ALIGNMENT OF AN EQUATORIAL MOUNTING
Dan Purrington
In my opinion the
three best methods are:
1.The Drift Method
This is the “gold
standard” and perhaps the most straightforward, but is time consuming, and frustrating
for some. For details, see a variety of sites including http://www.astro-tom/tips_and_advice/precision_polar_alignment.htm. Many other sites provide the directions,
which are very simple.
2. The GO-TO Method
This requires an
equatorially mounting telescope with a “GO-TO” capability. This is effective and relatively quick, the only problem
being convergence. See “Polar Alignment
by Iterating on One Star and Polaris,” by Michael Covington:
http://www.covingtoninnovations.com/astro/interating.pdf.
3. Clay Sterrod’s Kochab method
This is perhaps the
easiest method, especially if you don’t have GO-TO capability. It requires a lot of care in leveling, etc.,
in order to achieve tracking accuracy.
It depends on the fact that the NCP is on a line between Kochab (β Ursa Minoris) and Polaris,
which means that it works best if you can arrange to have Kochab
directly E, W, N, or S of the NCP. This
can be done with the aid of a planetarium program like The Sky. See “Precise Portable Polar Alignment” on
Sherrod’s site:
http://www.arksky.org/Kochab.htm