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Noise Halo

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#1 pnyxxpress

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Posted 17 February 2018 - 03:44 PM

What causes this noise halo on my images? I'm using a WO 81mm with a WO field flattener and reducer. I happens on both my Canons but it is worse on my older camera. It's a bit of an annoyance when creating a mask.

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#2 Tapio

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Posted 17 February 2018 - 04:10 PM

Are you using filters and if then does it remain after calibration?

#3 pnyxxpress

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Posted 17 February 2018 - 08:20 PM

No filters. This after stacking.



#4 Jerry Lodriguss

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Posted 17 February 2018 - 11:55 PM

What causes this noise halo on my images? I'm using a WO 81mm with a WO field flattener and reducer. I happens on both my Canons but it is worse on my older camera. It's a bit of an annoyance when creating a mask.

The dark line on the bottom is from the shadow of the mirror.

 

The large ring artifact is probably from a reflection or glare shining of some surface in the flattener / reducer and/or focuser, focuser drawtube, or adapter, or a reflection from one of the elements.

 

Jerry



#5 pnyxxpress

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Posted 18 February 2018 - 12:20 AM

Thanks. Looks like a process of elimination. I took a few wide field images tonight with a different lens and the subs don't have the halo. I''ll try my next session without the the reducer and see what happens. Hopefully it's not the main optics causing it.




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