Image Round Reflection

ZWO ASI2600MM DUO Askar FRA500 Request for feedback Artifacts Help Needed
1 reply•110 views
Asgardian92 avatar
Asgardian92 avatar
Hello everyone, noob here. Can someone might identified what this round reflection on my photos might be? Seems to appear on every  target that I shoot. I thought its was a dirty lens but that's not the case. My current setup:
  • Askar FRA500
  • ASI2600mm DUO
  • 2" filter wheel
  • LRRGB and Narrowband filters
  • 0.7 Reducer


thanks,

Jonny Bravo avatar
Jonny Bravo avatar
It's dust. One of the reasons we take flats is to calibrate that out.
Well written
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