Is it possible to write a script where AA6 will:
determine the centre of the field (plate solve) with the mount's RA shaft pointed north and the OTA also.
determine the centre of the field of another image with the mount rotated in RA by 6 hrs(90degs).
determine the rotational offset of the images to establish the centre of rotation of the camera/OTA combination
using the centre of rotation report the error in altitude and azimuth from the true and/or refracted pole so that the user can then adjust the mounts altitude and azimuth adjusters to properly align the RA shaft with the true pole?
Astroart and polar alignment
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- Posts: 275
- Joined: 10 Dec 2018, 16:23
Re: Astroart and polar alignment
Hello, I don't understand your method for polar alignment, but with a script you could implement the "declination drift" polar alignment.
Just search with Google: declination drift for the explanation of the method.
Then, with a script you could automatically place the scope in the correct position (using the ALTAZ - EQU) conversion functions, and take two images to evaluate the drift, using plate solve. If you don't know the method, I suggest to try it by hand 2-3 times. Many years ago I achieved to do it manually in less than 10 minutes, for my portable telescope.
Just search with Google: declination drift for the explanation of the method.
Then, with a script you could automatically place the scope in the correct position (using the ALTAZ - EQU) conversion functions, and take two images to evaluate the drift, using plate solve. If you don't know the method, I suggest to try it by hand 2-3 times. Many years ago I achieved to do it manually in less than 10 minutes, for my portable telescope.
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- Posts: 275
- Joined: 10 Dec 2018, 16:23
Re: Astroart and polar alignment
It would be similar to this method:
http://www.considine.net/aplanatic/align.htm
and:
https://github.com/ThemosTsikas/PhotoPolarAlign
http://www.considine.net/aplanatic/align.htm
and:
https://github.com/ThemosTsikas/PhotoPolarAlign
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- Posts: 275
- Joined: 10 Dec 2018, 16:23
Re: Astroart and polar alignment
OK, the idea is interesting, it's similar to two star alignment in modern telescopes. I suggest two zones at +80°/+85° in Dec (too close to the pole may cause issues with plate solving). The two zones could be easily selected "above" the pole, in the direction of the zenit (e.g. RA1 = Sideral Time + 3 and RA2 = Sideral Time -3).
The hard part are the formulas to find the actual centre of rotation and the formulas to translate it to movements in ALT-AZI of the mount base.
The hard part are the formulas to find the actual centre of rotation and the formulas to translate it to movements in ALT-AZI of the mount base.