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When I look through my polarscope and rotate the RA arm, the cross hairs stay in the same place but the image itself moves.  Is this a problem? 

I have tightened everything. 

Can you explain why the image moves?  Is there another adjustment I need to do?

Thank you,









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sorry didn't explain it clearly.

I did adjust the polarscope so that the cross hairs stay on the same spot of an object when the RA arm is rotated.  However the object itself seems to moves when the RA arm is moved.

I would have thought the object I am looking at wouldn't move.



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That sort of reads that the polar scope is not collimated to the mechanical axis of the insert that it fits into. So you rotate the RA and the object appears to rotate. Not sure how to get a polar scope out, have one but never attempted.

Would half expect some adjustment, but that depends on how good the machining is/was. In effect you have the reticule collimated to the poalr scope and then the poalr scope collimated to the RA axis. Quick look at mine and I cannot see anything to adjust the polar scope alignment but you are talking of 2 or 3 minutes and no idea what I was doing or actually looking for.

Anything on Astro Baby's site ? Tends to be a good source of mount set up and alignment information. Which reminds me I much go get information from there myself.

One other thing (me being thick I suspect) but the title is "Mr", what is "Mr" ?

Edited by ronin

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Do you mean the "images" etched on the glass of the polar scope rotate, rather than the stars?

If so, that is supposed to happen. It is so that you can rotate the mount/ polar scope in the RA axis to position the circle in the correct position, relative to the respective time and date, to then make adjustment to the altitude and Azimuth of the mount to center Polaris in the circle and thereby polar align your mount.

Sorry if that is not what you were referring to.

Edited by Uplooker

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Thank you for your answers. 

The title is "Mr" as I am new to the site and thought that they were asking my title as in  Mr/Mrs/Miss. 

It was actually a chimney that I was using to calibrate my polarscope and that is what moved as the RA arm was moved. 

The explanation that the polarscope is not aligned mechanically to the axis of the insert seems likely.  This would result in the polarscope not rotating about its own axis as the RA arm is moved.   The question is:  does it matter?  

I will be trying to answer my own question.  Grateful for any thoughts. 

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