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Accuracy ...?
I spent a frustrating night last weekend trying to polar align my mount on the pier. My problem is I don't really have a low western sky view to get the RA drift correct. Set the dec angle on the mount scale and hunted around all over the place but no matter what I did it kept drifting slowly westward (?) I think. Pulled down the instructions from here plus some other ideas to find the SCP etc.
So this weekend I made an inclinometer. Disk of ply, glued a full circle protractorI'd printed ages ago building Skeletope I and added a piece of alum angle on the back and a nice heavy pendulum. Today pulled back the covers and checked the dec angle against the weight bar. It was miles out !
If I set the mount according to the scale on the EQ6 head there is a ~3 degree difference ! It reads 40 degrees when I have 36.9 at the pendulum. And yes, the base is level in all directions.according to my builders level and the bubble on the mount. So just how accurate are these manufacturers scales on the mounts ? A degree or so I could expect but 3 degrees is quite significant in my books.
The Sky Gods are good tonight, no clouds !! I'm going to have another go shortly. I still don't have a good western sky but at least I'm leaning at the right angle hopefully. A wee bit of AZ adjustment might see me tracking close to polar and then the fun starts.
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