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Yet another polar alignment query - Losmandy G11 without a polar scope


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Good afternoon all.  I've recently upgraded from a Nexstar 5 on a single arm mount, to a 200PDS on a Losmandy G11, with a Berlebach Tripod.  It's gorgeous, and blumming heavy.

Having never had an EQ mount before, I'm struggling with polar alignment.  I have ordered a polar scope, as the observatory isn't going to happen until the next house, and I hope the PS will make life easier, but until that turns up I've been attempting to align using the Polar Align Assist routine within Gemini I. 

I can't for the life of me get it accurate.  I'm selecting a star near the East horizon, and one near the pole - Vega and Polaris have been a common pairing recently, and am completing the slewing task several times, each time only adjusting the altitude bolt when on polaris, and the azimuth bolt when on vega, and can't seem to get the accuracy I need.  Moving one axis seems to kick the other one out, and vice versa.  

When I get it as close as I can, I run PHD2 on my Orion SSAG, and after calibration get a warning that my alignment is out.  I haven't delved into drift align yet, as I've got to set up as quickly as possible and leave the scope imaging, without my intervention unless it rains (my wife had twins last weekend)...

Anyone able to furnish me with a panacea for all polar alignment ills? I don't need sub arc second accuracy, as i can guide out some error but it would be nice to be somewhere near accurate!

much obliged,


Jim

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The QHY polemaster seems to be the answer to the PA problems of everyone who has tried it - but at a cost (about £300).

One thing I have found that can get me close enough to run the PHD alignment program is using my telrad as a polarscope (a lot easier on the back than trying to look through the polarscope on the NEQ6 - not sure where it fits on the G11 mount) - the technique is detailed here.

HTH.

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When you set up for polar aligning, manually align the scope and mount north and center polaris in your main scope. Now do a 2 star align sequence using 2 other stars, Vega plus one other, don't use polaris as your second star. try this, as this is my procedure and I normally do not have any problems using my HEQ5 mount.

 

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That strikes me as weird. You can centre Polaris in the main scope no matter how well the mount is aligned. Then doing a 2-star align, will align the scope to the sky, but again, not the mount.

What sort of sub-length are you getting without trailing?

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makes sense - I'll give it a go this weekend, I've got a telrad in the shed somewhere...

it's only going to be an issue for the next month, then I'll be polar scoped up, and will hopefully have persuaded the wife that a small obby is a good plan...

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As said until a polar scope is fitted an accurate polar alignment is difficult, following the fitting of the polar scope then mount accuracy can be achieved. However the sequence of 2 or 3 star alignment is done using stars other than polaris. This is where I believe additional inaccuracy may be introduced.

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+1 for the PoleMaster.  I have had some difficulty with PA on my HEQ5, aside from the gymnastics needed just to see through the pole-scope.  I purchased the Polemaster last week and was out on Saturday evening for a first run and found it ridiculously easy to get very accurate PA.  I pushed it a little but still managed a 120second image with only slightly oval stars, 200seconds and they become eggs for sure.

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