Check it out! I can form a full sentence! Scopes: Explore Scientific 152mm f/8 Carbon Fiber Triplet, Obsession 15" Classic Camera: SBIG ST-8300M, SBIG FW8 Filter Wheel, Astrodon LRGB and 3nm Narrowband Filters Mount: AP900 Hang out with us at Mount Lemmon Sky Center
Quote:Maybe I should rephrase my question, and that is, what is considered excellent vs. good vs. okay polar alignment?
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Quote:Ron, wouldn't that be determined more by periodic error and focal length rather than polar alignment error? PA is just going to determine how long you can go without field rotation.
Quote:alpal, that kind of drift while guiding is usually caused by differential flexure rather than polar alignment error. if you have perfect guiding then as you point out you will have field rotation but there should be no drift.
if you turn off guiding and measure the drift then you can draw some conclusions about polar alignment.
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Quote: I have wondered, do Paramounts and AP mounts adjust smoothly and easily compared to Atlas mounts?