ArthurKay So, every time I flip the meridian I have to recalibrate.
The next time you have a chance to, do a guide calibration with a star east of the meridian. Check the Calibration Data (the circumscribed "i" icon) and note down the directions of the blue and red vectors that are drawn on top of the camera's x-y coordinates (white cross).
Then perform a GOTO to a star west of the meridian; this should move to the star through the pole (i.e., where a German mount performs a pier flip). Do not slew to the star on the west. Do a real GOTO. A slew will not do a pier flip.
Now do a guide calibration on the star on the west.
Check the calibration data picture again. Did both the blue and red vectors reverse directions, or did only the blue vector reversed direction?
There are two (perhaps 4) mappings between two spherical coordinate systems that will maintain continuous motion at the pole.
In one of the possible mappings (used by the majority of mounts), only the RA motor's direction is reversed after the pier flip.
In the second mapping (more rare in mounts), both the RA and the declination motors are reversed.
When you manually flip (with the flip switch in the Calibration Data panel) or when ASIAIR flips after an "auto meridian flip," the behavior is to only reverse (flip) the RA motor.
If both the blue and red vectors in the Calibration Data change directions after a pier change, you cannot just do a simple RA reversal. You need to reverse both motors.
During the v1.6 Beta program, ZWO added an option to also apply a declination motor reversal. But for some reason, that option vanished in the released version of ASIAIR v1.6.
Instead, what now appears is a "Recalibrate Guiding after AMF" switch in the "Meridian Flip Setting" window that you open from the Telescope Settings window (even though the window has nothing to do with the Telescope; it only has Mount settings).
You probably need to select this option for your mount. It takes more time than a simple "reverse both RA and declination motor" option, but at least you don't have to say awake to do it manually yourself.
Chen
