Quote:
Originally Posted by skysurfer
Well, when the telescope has a polar scope, just center the +6.9 star BQ Octantis which is only 10' off the pole.
I did this often, allowing 4 minutes exposure with 600mm FL with pinpoint stars without guiding. No lasers required.
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Actually if you also use the double star right near BQ and centre your polar scope crosshairs on a point that makes a slightly flattened isosolies triangle with them and on the Sigma Oct side... you will be within at least 2' of the pole
. This is how I have always polar aligned my Tak NJP mount (which is renowned for having an accurate polar scope). On a dark moonless and steady night this can be done in literally seconds (on unsteady moonlit nights it is harder to see these faint stars). I have done a
10min unguided exposure at 1140mm FL after doing this
The flattened isosolies triangle is getting flatter each year due to precession too, so in a couple of decades or so you will just have to point the cross hair at the midpoint between BQ and the double star and you will essentially have perfect PA in 10 sec - heaven!
Mike