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All star polar align

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#1 akulapanam

akulapanam

    Mariner 2

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Posted 19 January 2013 - 09:31 PM

This is the other issue I did ran into tonight. I did my eq auto align, went to my third star hit align mount and finished the process. Then I turned off the mount redid the eq auto align connected the camera and discovered that my polar align was pretty far off (max exposure 15 seconds).

Then I redid my polar align in live view and discovered that I had to do quite a bit of correction again. This time rather than turning off the mount I simply replaced my existing eq alignment stars. This seems to have worked ok as I'm getting 40 second exposures.

Is there anything I can do to get better polar alignment unguided?

#2 Motokid600

Motokid600

    Vostok 1

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Posted 20 January 2013 - 12:59 AM

I've been meaning to give this a try.

http://www.cloudynig...hp?item_id=2838

#3 cn register 5

cn register 5

    Viking 1

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Posted 20 January 2013 - 04:46 AM

The ASPA can be no more accurate than the initial alignment. If there's a problem with that then the polar alignment will not be good.
Using live view on your camera may help to get a good alignment because it's easier to get the stars centred accurately, both for the alignment and the ASPA.

There's no need to redo the alignment after the ASPA because the scope will adjust the pointing model by the amount of correction made.

Chris

#4 Motokid600

Motokid600

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Posted 20 January 2013 - 09:49 AM

You know I can never get the sync'ed star to go right back into the center. I use backyard EOS ( damn near a must have ) so I have a reticule overlay on my live view. And no matter how many adjustments I make ( Cpc1100 on a Mitty wedge ) the sync'ed star always falls about an inch to the right of center on my screen. Maybe I'm doing something wrong?

#5 rmollise

rmollise

    Hubble

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Posted 20 January 2013 - 10:50 AM

If it's not easy to get the star in the center using the wedge alt/az adjusters, you need to choose another star. Like one closer to the intersection of the Meridian and Celestial Equator...






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