| This polar finderscope works with the Losmandy GM-8, G-9 and G-11 mounts only. It threads into the polar axis and works in both Northern and Southern hemispheres. A red LED illuminator powered by two miniature LR41 watch batteries (supplied) illuminates the polar alignment reticle. The illuminator can be unthreaded from the finder, if desired, and the illuminator port sealed against the entry of dust by a knurled plug when the illuminator is not in use.
In the finder is an etched reticle with two star patterns covering the north and south celestial poles. No calculations are needed to use the polar scope. Simply rotate the polar scope until the appropriate alignment stars approximately line up with the etched pattern for your hemisphere, adjust the mount's altitude and azimuth knobs to move the mount until the stars fall precisely in the positions indicated in the reticle, and that's it. The polar axis of the scope is now lined up with the appropriate celestial pole.
While the alignment will not eliminate the need to guide your scope during long exposure astrophotography, it will considerably reduce the number and magnitude of corrections needed due to polar alignment errors.
For a more detailed description of how to use the finder, including images of the illuminated polar reticle, click on the "Polar finder detailed instructions" link above. The instructions show index marks showing where to place the appropriate alignment stars for the years 1990, 2000, and 2010. However, the current version of the polar finder has the correct indexing marks for the years 2005, 2010, 2020, and 2030 (and can be extrapolated further), assuring accuracy for decades to come.
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