ZWO Filter Wheel not holding center Position during Imaging

ZWO EFW 7 x 2″ Filter Wheel Troubleshooting
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Rick Fair avatar
Rick Fair avatar
=MsoNormal Slipping during imaging session.  This issue is that the filter has started to slip when imaging.  The filter is not lined up with the camera sensor and shows a line in image. When I manually rotate filter it centers back up and image is ok, but after about 5 300 sec images it starts to slip and filter moves and there’s a dark edge of on image showing the side of filter wheel filter frame. Any ides on how to fix tks
Bruce Donzanti avatar
Bruce Donzanti avatar
You can recalibrate it and see if that fixes the problem.   If it is new, just return it and get a new one and not aggravate yourself over it.
Rick Fair avatar
Rick Fair avatar
I did recalibrated it several times, also I got it from ZWO Directly. Ive created a support ticket. I thought if anyone else had one with these issues there my be a simple fix…
Andrew Barton avatar
Andrew Barton avatar
I have had similar issues in the past. There is a setting in the driver or your acquisition software that will tell the filter wheel to move in only one direction. I find this setting makes the filter wheel perfectly consistent. I have had this problem with filter wheels from other manufacturers as well.

CS, Andy
Helpful
Brian Puhl avatar
Brian Puhl avatar
Does it have 7 filters in the wheel?  You could be unbalanced if there isn't a full filter set in there.
Bill Gwynne avatar
Bill Gwynne avatar
Rick, the only time I've ever had mine not work correctly is when a filter was screwed in too far and it was scraping on the other side. I've never had it move out of position once it was set but would be curious to know what the fix is when you get it.

Bill
Well Written Respectful Concise
Eyecon avatar
Eyecon avatar
Brian Puhl:
Does it have 7 filters in the wheel?  You could be unbalanced if there isn't a full filter set in there.

@Rick Fair I have the same EFW with screw in 2” filters and I’ve only seen this kind of behaviour only when the wheel is unbalanced just as Brian suggested. Did you try redistributing the filters more evenly around the wheel?
Concise
Arny avatar
Arny avatar
Rick Fair:
=MsoNormal Slipping during imaging session.  This issue is that the filter has started to slip when imaging.  The filter is not lined up with the camera sensor and shows a line in image. When I manually rotate filter it centers back up and image is ok, but after about 5 300 sec images it starts to slip and filter moves and there’s a dark edge of on image showing the side of filter wheel filter frame. Any ides on how to fix tks



I had the same problem and reason in my case was, that I had 2 empty slots in the 7x2" and did not use them opposite of each other - so a disbalance in the filter wheel pulled the wheel down leading to the same effect.
Adel Kildeev avatar
Adel Kildeev avatar
I had a similar issue with EFW-5, but the problem was in the non-standard filter (too thick), after the filter’ s replacement works fine.
Mickaelle (kaelig) avatar
Mickaelle (kaelig) avatar
If you add a thick ring, you could change the mechanic position of the wheel or rotate your optic train in the eyepiece holder. It could help to change the move of your filter wheel. It is just an idea.
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