hassle-free polar alignment

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AstroDude
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hassle-free polar alignment

Post by AstroDude » Mon Jan 07, 2019 4:54 pm

Tired of wasting time getting your polar alignment done, while trying to reach down to 00:00:05 arc/sec instead of 4 arc/min..
Have you had enough of using ASPA and your still way off, or bending over twisting your neck looking through the polar scope and winging it, or even the tedious Drift alignment method, then......
try Sharpcap 3.2 Pro polar align software routine .follow the link below to a EZ to follow youtube tutorial.

https://youtu.be/ivlgbgNIeTU

(Sorry for posting twice , Robin G)

Mitch/ Astrodude

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oopfan
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Re: hassle Free polar alignment

Post by oopfan » Mon Jan 07, 2019 6:03 pm

Nice video Mitch.

Just a minor point: "hassle Free" is usually hyphenated "hassle-free". When I initially saw this topic the word "Free" caught my attention. I said "Oh wow, 'free polar alignment'". Then I saw "hassle" and thought "Oh cool, this free software is named 'hassle'".

I suspect this was a clever marketing gimmick on your part :D

Brian

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Re: hassle-free polar alignment

Post by admin » Mon Jan 07, 2019 9:14 pm

Hi Mitch,

thanks for making and sharing that video – it's excellent! I have taken note of Brian suggestion and change the title of the thread slightly to make hassle-free hyphenated.

Just a couple of points where your preferred technique differs a bit from mine. First I think I would probably turn up the camera again more rather than using the digital gain in the star detection settings although that is a matter of preference and if you got settings that work then obviously keep using them. Secondly I believe that when the star you are tracing goes offscreen during the adjustment phase, SharpCap should automatically select another star that is still on screen for you to continue to work with so it should be unnecessary to restart at that point. If you happen to get clear sky before I do I be interested to hear whether that's the case or whether there's a bike there that I need to fix.

Thanks again, Robin

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turfpit
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Re: hassle-free polar alignment

Post by turfpit » Tue Jan 08, 2019 11:21 am

Mitch

Interesting tutorial - appreciate the effort in doing it.

I found the weak part of the polar alignment process is the course threads on the alt/az adjusters plus the play in my mount. I use ASPA for polar alignment. Once I have the finder scope and telescope aligned on a distant land based object I swap eyepiece for imaging camera. Then I carry out a 2 + 4 mount alignment and the ASPA using the capture screen. So there is only one uncomfortable viewing up the polar scope - prior to mount alignment.

ASPA is useful as it works without sight of the Pole Star. Plus it is available across multiple capture programs & other operating systems such as Linux, Pi and Macintosh.

Anyway, hope you have a great 2019 for imaging.

Dave

astromusic
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Re: hassle-free polar alignment

Post by astromusic » Tue Jul 30, 2019 2:42 pm

So, is the ASPA something proprietary to Celestron scopes, or is there a way to use it on all scopes?

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turfpit
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Re: hassle-free polar alignment

Post by turfpit » Tue Jul 30, 2019 4:40 pm

All Star Polar Align is a facility in Celestron Nexstar handsets to allow polar alignment of the mount without sight of NCP by using any star.

Synscan handsets have the same facility, see page 38
https://inter-static.skywatcher.com/dow ... 8V1-EN.pdf

I would expect other manufacturers would have a similar facility but the name would be different.

I have used ASPA to good effect on my CG5 and AVX mounts.

Dave

motoflatdrag
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Re: hassle-free polar alignment

Post by motoflatdrag » Wed Feb 05, 2020 7:36 am

The video is private.

scpanish
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Re: hassle-free polar alignment

Post by scpanish » Fri May 01, 2020 6:30 pm

It would be nice to be able to view the video!
However, I've been using the SharpCap PA tool and it is the **BEST** PA tool I've used. I never was able to use drift well enough to do consistently better than 90 sec unguided exposures (at 2800 and 1750mm FL). Some orthogonality error made drift alignment difficult. I am generally guiding, but can do up to 4-5 minutes without.

I find that I can set my AP1200, with effort, to 5sec accuracy. However when I restart the routine and rotate back to the starting position, it is off to 20sec or thereabouts. So I redo it. Is there an iterative procedure that will give best results? Maybe in that video that we cannot see?

thanks for the great PA routine!

Steve

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turfpit
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Re: hassle-free polar alignment

Post by turfpit » Fri May 01, 2020 7:08 pm

Steve

This is the website of the owner of the video https://www.astrodude.com/index.html. There is an email link on the left hand side.

Dave

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Re: hassle-free polar alignment

Post by admin » Sat May 02, 2020 2:31 pm

Hi,

If you get a slightly different result on a second line when rotating back to the original position then the most likely cause is that the camera is moving very slightly as the mount is rotated – make sure that all cables are secured and that the guide scope and camera are securely held. Even a dangling cable can lead to this sort of problem. Mind you, it's probably not really worth worrying about – 20 arc seconds of misalignment would give you a maximum declination drift rate of about five arc seconds per hour, so unlikely to show up unless you are taking subs of 15 minutes or longer.

Cheers, Robin

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