bb001 2021/05/25 21:31:28 Solve succeeded: RA:12h16m53s DEC:-8°50'32" Angle = -59.562, Star number = 28
2021/05/25 21:31:28 [AutoCenter|End] Too far from center, distance = 330%(8.82247°)
2021/05/25 21:31:29 [AutoCenter|Begin] Auto-Center 8#
2021/05/25 21:31:29 Mount slews to target position: RA:12h16m53s DEC:-17°39'53"
2021/05/25 21:31:39 Exposure 1s
2021/05/25 21:31:41 Plate Solve
2021/05/25 21:31:43 Solve succeeded: RA:12h16m52s DEC:-8°56'6" Angle = -59.5745, Star number = 24
You may be so far off in declination after the flip that ASIAIR is confused about the direction to auto-center. Typical mounts will be within a degree of declination after a flip.
Recall that ASIAIR does not really flip anything -- it simply commands your mount to GOTO a specific RA and declination coordinate (should be about 12h 17m and -17.6º in your case), but after your mount's motors has moved to that position after the pier flip, a plate solve showed a good RA, but the declination of the stars is a whopping 7.5º off from the mechanical declination.
I.e., you should see the same problem even with just the hand controller, with ASIAIR completely out of the picture.
There are at least two things that can cause that.
One is that the dovetail plate is tilted in the declination direction. A good bubble level or a cheap $20 digital inclinometer should get you within 0.5º. Move the mount so that your OTA points to the east horizon using a GOTO (RA = LST+6 hours, declination = 0º, pier side west) and then do a GOTO to the west horizon (RA = LST-6hours, declination = 0º; pier side should flip between the GOTOs) and compare the OTA angles from horizon.
If you have a 8º or so difference, that is your problem. Usually, you need to do this before locking down the bolts that hold the dovetail saddle to the declination axis, but 8º seems a rather large error. If the east and west pier side is really producing this big an error, check with the manufacturer to see how you can remedy it. You can usually loosen the dovetail saddle bolts and fine tune, but 8º is larger than I have experienced. I guess that large an error is possible if you are using imperial bolts when the saddle is drilled for metric holes, for example. Or using M6 bolts in an M8 hole.
The second possibility for discrepancy in declination between east and west pier side is that your polar alignment is off. But agin, you would need to be some 4º off to produce a pier side discrepancy of 8º. Since you did not complain about field rotation (should be obvious with a 4º polar alignment error), this is probably not your problem.
There may be other mechanisms, but you should be able to track it down without ASIAIR even in the picture.
Chen
