Darrel,

As the coordinates of Polaris are NOT at 90 Dec (they are Dec +89 15 50.8 RA
02 31 49.08), this is where your 'spinning Polaris' theory fails. Polaris
is offset from the true pole by 3/4 of a degree, and though the Lx200
electronics tell you to point there as if it were the pole when aligning,
there is a bit of correcting in the inside to compensate for the offset.

A scope truly 'polar aligned' does not point to Polaris, but to a point at
90 Dec and any RA you want (because they all converge at a point there). If
you are properly aligned, and set the scope to 90 Dec and spin it around as
you describe, Polaris should circle the pole point also because it does not
sit on that point. Because Polaris is 3/4 degree away from this point, you
need a pretty wide field of view to watch it circle (over 1.5 degrees).

While further alignment and othoganality issues may be present in your
setup, the fact that Polaris is not spinning quietly upon itself is not a
positive indication that this is so.

Hope this helps, (and if I am mistaken in my explanation, someone please
correct me!)

Anthony J. Kroes
Green Bay, WI


> -----Original Message-----
> High Desert

> amount in relationship to the axis of the OTA. If I put my LX-200 on my
> wedge, and then set the Dec to 90, and then align the wedge so
> Polaris is in
> the center of the eyepiece, I should be able to spin the mount in RA and
> Polaris should stay centered. If the star produced an ellipse or
> a circle
> this would be an indication that the scope was not orthoganal.
> Naturally I
> should be able to remove any movement in one plane with the Dec axis, but
> the other would have to be removed by adjusting the OTA alignment
> screws at
> each side of the tube. Anyone see anything wrong with this
> thought process?
> Am I missing something?
>
> The reason I ask is, I tried this last night, and I never could
> get the star
> to even stay within the FOV for one rotation. No adjustment
> would make it
> better, only worse. This was using a 40mm EP with a FOV of about
> one full
> degree. What am I missing?
>
>
> Darrell

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