I've finally conducted the testing. Conclusion is that in test 2, the filter wheel is not aligning at the same spot. I believe this is due to bi-directional movement. I did not open the filer wheel to check as I didn't want to mess up the tests. What I think is happening here is in test 2, you move forward from slot 6 to 7. But then when shooting flats, I had it move from slot 0 to 7, and I think it just does this reverse to take the shortest distance. But the sensor that detects the alignment is only reliable turning one direction all the time.

I'll be sending these findings to ZWO to see if they can force the EFW to move in only one direction. If it's possible to fix this in the driver, then we should do that for sure. I also had this issue with my ZWO 1.25 8 slot filter wheel, so I think they all work the same way and this is an issue across the board.

Test 1
Move EFW to Slot 7 OIII
Shot OIII bin 2 light no filter move
Shot OIII bin 2 flat no filter move



Test 2
Move EFW to slot 6
Shoot OIIi light filter move to slot 7
Move EFW to slot 0
Shoot OIII flat filter move to slot 7


Test 3
Move to slot 0
Shoot OIII light filter move to slot 7
Move to slot 0
Shoot OIII flat filter move to slot 7


Test 4
Move to slot 6
Shoot OIII light filter move to slot 7
Move to slot 6
Shoot OIII flat filter move to slot 7


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