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Easy, fast polar alignment
On the weekend, the group that we went with doing astrophotography had a number of new members with new mounts and new scopes. Confusion reigned when they couldnt do photography and none had a great grasp of drift alignment of even rudiementary polar alignment. During this time with in accurate Az/Dec graduations on mounts etc, I found an easy way to polar align in a few minutes and if you have an accurately aligned PAS (polar scope) with the mount, very accurate.
Usually the scopes had an 8x50 alignment scope with them. Now this field of view in this scope will place octans within 1/4 the field of this scope. Align your mount with a compass and inclinometer (for dec), then when dark, release the RA clutch and slowly slew the scope backward and forward while looking through the finder scope.
When octans is sighted adjust the dec so that the bottom two stars of the asterism are just in the field of view with sigma octans toward the middle of the finder scope. Lock the RA clutch and see how far off a straight line through your mount the scope is now pointing away from true North. Unlock the bolt holding the mount to the tripod and swivel the mount an equal number of degrees to the east or west. Tighten the bolt and again look through the finder scope. reitterate the last steps until mount is ligned up with finder scope image of octans.
Now look through the PAS and Octans will be dead centre in the PAS. Make small adjustments to ALT and AZ and you are polar aligned.
Usng this method I had no drift in 10 min with 8" SCT and it was done in 5 min from the start of the procedure.
This method assumes polar scope is deadly accurate and aligned with the axis (see manual), finder scope and main scope aligned and you are roughly polar aligned to start with (compass and right dec settings used).
Its easy because most people cant find octans in a cocked hat let alone a PAS, when its dark and they are on their knees. But if this technique is used its easy to recognise octans in the PAS.
Hope this helps
Contact me if this doesnt make sense
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