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I am looking again at the method I described earlier (believing it was what PoleMaster is doing), and the patent..
In patent they are mentioning all sorts of things, and this reading is additionally confused by bad translation into English.. I am sure even patent attorney would have been puzzled (or maybe not..).
Anyway, I am not sure the existence of patent is relevant for amateur activity at all – firstly, because the aligning method of two rotating axles is nothing new and basically a common sense issue, and in public domain for a long time. Secondly, no one here is trying to copy, manufacture and/or sell the product as competitor.
Finding the point where the polar axis is pointed at is accomplished with rotation by 180° all right.. mechanical setting circles can be used for better accuracy, or perhaps the bubble level on the DEC axis .
To find the celestial pole, however, it is better to use couple of stars, located around the pole (it is easy to recognize the asterism around sigma Octantis, and all those stars should be used, perhaps others at the other side of the pole as well).
They should be marked on the screen (and their positions stored) at their starting positions and then the tracking should be stopped. After some time the image on the screen will rotate… and the same stars should be marked again as end positions.
Software needs to place the joining lines between stars start and stop positions, calculate the mid points and then place the lines through those points perpendicular to joining lines. The intersection between all perpendicular lines is true celestial pole.
The vector defined by the point where polar axis is aimed (start) and the abovementioned intersection point (end) determines the amount and direction (negative) to move the star image (by adjusting the mount elevation and azimuth screws) from current marked position to the new one (indicated by software).
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