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CG-5 polar scope alignment

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#1 James Cunningham

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Posted 06 March 2011 - 02:12 PM

I have a CG-5 mount and purchased a polar scope for it. The instructions talk about moving the dec back and forth to get it aligned. Just how important is that? My neighbor who has the same mount has never aligned his polar scope and his gotos are great. We had first light with my mount last week and the gotos were fine. I tried to follow the directions and I got close but not quite.

#2 PHampson

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Posted 06 March 2011 - 03:12 PM

As long as you're reasonably close, polar misalignment doesn't really affect gotos. Folks do fine just sighting Polaris through the borehole without any polar scope. The alignment procedure adjusts for any polar misalignment for goto purposes. It will affect your tracking however, especially if you're trying to do relatively long exposure astrophotography. The DEC drift in that case will become very apparent and have to be guided out if you want nice round star images.


Paul

#3 Trev

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Posted 06 March 2011 - 04:11 PM

I've never felt the need to get one with the ASGT for visual you can just give it a rough polar alignment through the bore hole and then the alignment procedure takes care of refining the alignment.

#4 mcoren

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Posted 08 March 2011 - 12:56 PM

I also bought a polar scope when I first bought an AS-GT CG5. I can't tell you how many good hours of observing time I lost trying to get the polar scope itself aligned properly. And then, just from being carried between the house and the backyard (not even transporting in a car), it would shift and need to be aligned again! :bangbangbang:

Eventually I just removed it altogether and was much happier. As others have said, sighting Polaris through the polar scope opening in the mount gave sufficient accuracy for reliable GOTOs and good enough tracking for visual observing.

#5 rmollise

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Posted 08 March 2011 - 05:19 PM

I have a CG-5 mount and purchased a polar scope for it. The instructions talk about moving the dec back and forth to get it aligned. Just how important is that? My neighbor who has the same mount has never aligned his polar scope and his gotos are great. We had first light with my mount last week and the gotos were fine. I tried to follow the directions and I got close but not quite.


You do not need to use the polar scope for good go-tos. Sighting Polaris through the hollow bore is more than good enough. Imaging? The AllStar routine in the HC is better. All in all...the CG5 polar scope makes a good paperweight. ;)

#6 jrsmith

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Posted 08 March 2011 - 05:29 PM

i just get polaris in finder and sometimes in low power eyepiece...seems to be fine!? :)

#7 James Cunningham

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Posted 08 March 2011 - 06:13 PM

How are your gotos with just finding Polaris in the finder? I would think they would be a bit off. The polar scope and the finder are not on the same line of sight!

#8 rmollise

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Posted 08 March 2011 - 06:15 PM

How are your gotos with just finding Polaris in the finder? I would think they would be a bit off. The polar scope and the finder are not on the same line of sight!


You thunk wrong. :cool:

A buddy of mine, a newbie, came up to me at the dark site one evenin' and said, "Unk Rod...got a problem...my go-tos are great, but the tracking sucks." I gave it a look-see. Turned out the Polaris he'd aligned on was really Kocab. :lol:

#9 avarakin

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Posted 08 March 2011 - 08:26 PM

How are your gotos with just finding Polaris in the finder? I would think they would be a bit off. The polar scope and the finder are not on the same line of sight!


You thunk wrong. :cool:

A buddy of mine, a newbie, came up to me at the dark site one evenin' and said, "Unk Rod...got a problem...my go-tos are great, but the tracking sucks." I gave it a look-see. Turned out the Polaris he'd aligned on was really Kocab. :lol:


I guess he heard somewhere about Kocab polar alignment :roflmao: [If someone does not know what Kocob alignment is: it is used mostly for Astrophotography to align mount not with Polaris, but with true North pole, and Kocab plays very important role in this procedure]

Alex






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