Roland's polar alignment method

Derek Wong <dawong@...>

A repost of Roland's polar alignment method (with his permission):

...actually, I use another method to achieve accurate results, a
modification of method 3 in the manual. I choose a star that is close to
the meridian overhead, and center the crosshairs on it. Then I change
the clock time by 1 hour and enter the same star on the hand control.
The telescope now slews to the other side of the mounting, and the star
will be offset in declination by some amount (the star can also be off
the crosshair in R.A. but this is not due to polar alignment, rather it
is due to non-orthogonality of the telescope vs. the mounting). To polar
align, the star is moved half way to the center of the crosshair by
turning only the altitude adjuster. The star is now brought the rest of
the way with the buttons, and a recal is done by pushing button #9. That
in effect sets the altitude of the mounting. If done properly, you don't
need to do it any more times, but you could do it again by resetting the
clock time to the original hour and slewing to the same star again on
the other side of the mounting. A final fine adjustment can be done the
second time. You can also adjust the orthogonality of your mounting by
shimming up one of the mounting rings until the star comes in in R.A

The azimuth setting on the mount is done by picking a star in the north,
and then slewing to a star in the south at similar right ascensions.
Bring the star half way to the crosshair with the azimuth adjuster, and
the rest of the way with the buttons. Then hit #9 button to recal the
position. This way, the two adjustment axes are done totally
independently. It is highly accurate and very fast. I can do it in less
than 5 minutes and be dead on all night long.

Roland Christen

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