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Using Sky Vector to fine tune polar alignment

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#1 tr4driver


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Posted 29 March 2011 - 11:39 AM

Greetings everyone.

I hope I'm posting this in the correct forum. I have a Meade fork mounted 8" SCT with a Lumicon Sky Vector computer and encoders. I had always assumed that the Lumicon and the JMI (NGC-MAX) computers were the same; however, I recently came across instructions for the JMI system that included a section on how to use it to precisely set the polar alignment of the scope. Apparently there's a menu item specifically for this in the JMI computer that does not appear to be in the Lumicon computer.

Basically, the process is a follows:

1. Set computer to EP (perfect polar alignment)
2. Polar align scope
3. Turn computer on and use the 'STAR FIX' command to align with a star
4. Select the 'POLAR ALIGN' command

At this point, the computer will guide the scope to Polaris. When the guide is complete, you adjust the altitude and azimuth of the scope to bring Polaris into the center of the eyepiece (if it's not already there), then repeat the process until there's no error.

Now finally my question - Is there any reason why I couldn't do the same thing without the special menu command? I could simply select 'GUIDE MODE' (to Polaris) after my 'STAR FIX' and adjust altitude and azimuth, reset the computer and start over until after the initial 'STAR FIX' I get no error when guiding back to Polaris.

This all assumes that I'm using a single star to initially fix the position.

I would greatly appreciate any help/comments.



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