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Interesting conversation!
I have often wondered how you would go about automating polar alignment. I think without a CCD/Camera feedabck system it would be fairly inaccurate but not impossible.
Having used TPoint with the PME, the process of polar alignment is fairly simple.
1. Level the mount as best you can
2. Point roughly to SCP
3. Home and point telescope to a star as near the home position
4. Take live images and move DEC/RA manually until star in FOV.
5. Center star on CCD chip using Maxim DL
6. Sync
7. Start new TPoint model (6 points minimum)
8. After having slewed to and centered all 6 stars, Tpoint will provide DEC/RA adjustment info fro the PME.
9. Adjust mount accordingly
10. Your done.
Mind you this is the process with a PME as TPoint provides the exact number of tics to move the RA and DEC adjustments.
This will give you a fairly accurate polar alignement but not perfect.
The above process takes about 15 minutes.
It would be fair to say that if TPoint knows exactly what adjustements to take, there would be no problems sending a signal to a couple of servo motors to make the adjustments in tics.
Keep in mind, as soon as you do make adjustemnts you effectively have to re-do the TPoint model. This is a reiterative process to fine tune polar alignment.
To get spot on polar alignment and for pro-track to work effectively you need a 300 point + model to work with, not to mention tweaking the terms and eliminating outliers in your sample size. In my experience this is worth doing when you have a permanent obs, but an overkill for field use. I find a 30 Tpoint point model gets you close enough in the field.
So in motorising the polar alignment and given that the above procedure takes 15 minutes, one would ask if its worth the effort.
The only benefit you would gain in the field is that you would not have to get up from your chair to do it :-)
Mark
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