Why are there two circles in this image from an SCT? I also have a refractor that uses the same filter wheel and camera where this doesn't occur.
I'm pretty certain this is also after correctly focusing.
1. Meade 10" F10 SCT
2. SCT crayford adapter
3. Feather Touch crayford focuser
4. Optec 0.62 recucer
5. 50mm extension tube
6. 15mm extension tube
7. ZWO OAG
8. ZWO 2" 7 place filter wheel...I believe set to luminance filter in this image
9. ZWO 1600mm main camera
Edited by adamchicago, 27 September 2020 - 05:15 PM.