It appears after some testing with Jasem that the RA values during slewing are changing rapidly from say 2hr to 14hr.

It appears there is jitter in the dec encoder which is changing the sign from + to -ve randomly and that affects the calculation for the coordinates.

We tried an updated driver that accounts for the jitter but it continued to show similar behaviour in my indoor testing today.

Out of curiosity instead of leaving the Dec access at home position I changed it to + or - 1 or something more or less than 0. I did similar for the RA access. In that mode all the SLEWs showed correct Ra values as you would expect at say x800 speed. I also tried the polar alignment module with these slight offsets to the starting position and it worked consistently every time (indoors under simulation) did not matter if I was slewing east or west or the speed of the mount. 

I removed the offset and began in the home position with encoders at 0.00 inn both axises and polar alignment would fail sometimes. It failed precisely at the time the RA values jumped around probably related to the dec jitter and the message mount aborted changed speed came up. I the checked again with my little offset and again it worked again consistently.

Might help some of you whilst it can be figured out, I cannot test outdoors I haven't seen the clear sky in 3 months.

Jasem is working on it.

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