Ok, here is an example of a really bad version of the effect. This was a test just out my window with the Hasselblad 350mm. These ship lights are extremely high intensity, but this is still not an effect I like to see! I have also seen it occasionally with the 120mm, but not that often. Only in night shooting with very strong lights in the frame. I would expect this with filters (I had it with the UV/IR filters on the M8), but a bit disappointed to see it with the S2 and no filters. I am willing to put up with it in exchange for the superlative performance in all other aspects, however.
Or maybe there are just a lot of ghosts and UFO’s in Iceland? Also a possibility…