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Brendan,
Something wierd is happening for me - Tpoint, MaxPoint and PEMPro all disgree. When I do a 3 star alignment and go to the third star pointing is off by about 2-3 arc minutes - maybe its cone error, maybe its alignment error. I tend to think if the error in my 3rd alignment star is about 2-3 arc minutes that should also be my polar misalignmnet error.
MaxPoint concurs with this, but Tpoint disagrees and doubles the error margin and says its in opposite directions (both run on 120 evenly distributed stars)! One run of PEMPro says spot on another a day later says adjust by 15+ arc minutes - so I don't understand why I am seeing so much variability on a permanently, pier mounted setup!
I tracked Jupiter a few days ago and saw about 30 arc seconds drift in over an hour - that's when I remembered the drift formulea to double check my results. Regardless when professional level software disagrees - I put it down to user error and try and gather more data before I adjust!
BTW - is my thinking that once I align on two stars the third alignment star's misalignment should be a solid indication of the sum of mis-alignment and cone errors?
Matt
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