I am unable to get a star near the meridian and just above the celestial equator to not drift for more than 3 mins when performing an AZ adjustment.
I assume that you mean drift in Declination, is that correct? If the star is drifting in declination you may be adjusting the azimuth in the wrong direction each time.
You can also do another easy test of azimuth this way:
First go to a star overhead near the zenith on one side of the meridian (example: star on the east side of the meridian, scope on the west side). Center the star, using the NSEW buttons, exactly on your chip or use a crosshair eyepiece to center and press Recal.
Next, go to a star further east but not too close to the horizon. Ignore any pointing error in RA, but now bring the star to the Dec center line by turning the Azimuth axis. Now send the mount back to the first star overhead and it should be very near the crosshair. You can move it to the crosshair again via the NSEW buttons and do another Recal.
Finally send the mount back again to the star in the east and it should be very close to the Dec center-line (ignore any offset in RA). You can then do a final touch-up of the azimuth to bring the star to the Dec center-line.
This method of setting the azimuth axis results in the same performance as the azimuth adjustment in the classic drift method. You can check the drift at the celestial equator near the meridian. I would expect zero drift using the above method. I have done this adjustment many times and always got excellent results (it is part of my Quick Drift method).
If you still have any drift in 3 minutes, then something else is wrong - perhaps the mirror in your scope is shifting slightly.
From: Bruce Donzanti donza2735@...
To: ap-gto <ap-gto@...
Sent: Fri, Dec 15, 2017 9:15 am
Subject: Re: [ap-gto] Need advice with new Mach1GTO: Polar Alignment and drifting
Yes- completely flush- no separation
To recap the scenario......
After balancing and being level, I do a rough PA and then attach the RAPAS and adjust the ALT and AZ to match the app. I then slew to a bright star, center it, and do a re-calibrate. When I slew to any DSO, none are centered and many are out of the FoV completely even though the scope is in the general area. So, I have been assuming that I need to check the accuracy of the RAPAS and perhaps re-align it slightly. This is when I was trying the drift method which I am having trouble doing - meaning, I am unable to get a star near the meridian and just above the celestial equator to not drift for more than 3 mins when performing an AZ adjustment. I then checked the ALT with a star low in the east near the celestial equator and that was no problem as the star did not drift for the 10 mins after a small Alt adjustment. I then went back to check AZ but drifting keeps occurring regardless as to what adjustments I make, even up to the point where I make such dramatic shifts in AZ that Polaris is almost off the scale when I look at it through the RAPAS. This is confirmed when I removed it and looked through the PA scope hole as Polaris was way off center.
I hope this makes sense as I cannot think how else to explain the problem.