Polar alignment near tropics

Using SharpCap's Polar Alignment feature
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swap_saraf
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Joined: Thu Jan 30, 2020 8:48 am

Polar alignment near tropics

#1

Post by swap_saraf »

Dear friends,

I wanted some help to know if the Sharcap Pro can help me for Polar Alignment when I am below the tropic. My latitude/longitude is 18 degree North and 73 degree East. I had been using a skytracker and recently moved to a skywatcher eq6r. I can view the polaris and very few stars near the Northern sky. However, as the North star is just 18 degree above the horizon my north sky near the horizon is bright with city lights. Will the data be sufficient for Sharpcap to analyze for PA?

Thanks
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admin
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Re: Polar alignment near tropics

#2

Post by admin »

Hi,

The best answer is to try it out. I know people use it at about 30° latitude, but I haven't heard of anyone using it at your latitude yet. If you can get enough stars visible around the polar region then it should work. Remember to enter your latitude in the options and turn on correction for atmospheric refraction when polar aligning as that will be significant so near to the equator. No need to purchase a pro version just to try this out – you can run through most of the polar alignment routine up to the point where it tells you how far out your alignment is in the free version. If it works smoothly that far then the final alignment stage should also work well.

Cheers, Robin
swap_saraf
Posts: 2
Joined: Thu Jan 30, 2020 8:48 am

Re: Polar alignment near tropics

#3

Post by swap_saraf »

Thanks Robin, I will try it and see if it the stars in FOV are good enough
Curtis2010
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Joined: Wed Jun 17, 2020 2:04 am

Re: Polar alignment near tropics

#4

Post by Curtis2010 »

Related question. I live in Panama at about 09N. Polaris is rarely visible from anywhere on land (...sometimes at sea). Must polaris be one of the stars captured for polar alignment?
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admin
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Re: Polar alignment near tropics

#5

Post by admin »

Hi,

in theory there is no need for Polaris to be one of the stars, but you do need to be picking up stars within about 5° of the north celestial pole – if you are not able to see Polaris at 9° altitude then I'm not at all sure you will be able to see fainter stars at 12 to 14° altitude. There's nothing stopping you from testing however – you don't need a SharpCap Pro license to use the polar alignment up as far as the point where it tells you your alignment error. If you can get that bit to work reliably then you might be in luck.

Cheers, Robin
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