New answers tagged halos
You applied surplus of sharpening. Sharpening means for a computer to find a lightness transition and make the dark part of it darker and the lighter part lighter. If you apply disastrous amount of sharpening (as you clearly did) you are guaranteed to get those artifacts - the ligher part will become clipped white and the darker part will become clipped ...
Cleaning the lens is important, but it looks to me like your issue is compression artifacts. Check your camera settings to see if you can increase the quality of images saved or shoot in RAW.
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