Reflections?

[Anthonyexmouth]

Set NINA off to do it's thing last night. First target the Flaming Star and then at 01:00 the Leo Triplet. The triplet stack and barely visible in the subs has this weird glow pattern on the right with a bit of a whippy tail thing and funny arch artifacts. All streetlamps were off at that time. I wasn't up so can't know for sure what it was but does anyone else have any idea? I can't see the arches in the Flaming Star image or subs. 

Here's a double nuked screen grab from Pixinsight. 

[Fegato]

Looks like severe vignetting on the right? - no chance the image train moved somehow?  Sorry, no idea with the other patterns

[Ratlet]

I usually do the same troubleshooting for weird artifacts, blink through the subs to make sure there aren't any dodgy ones, maybe some cloud or a light shining on part of one of the images.  If that's good stack the lights on their own, then add darks, then bias and flats.  Most of the time I get trippy results it's either a dodgy sub or a dodgy dark/flat.

[Anthonyexmouth]

9 minutes ago, Ratlet said:

I usually do the same troubleshooting for weird artifacts, blink through the subs to make sure there aren't any dodgy ones, maybe some cloud or a light shining on part of one of the images.  If that's good stack the lights on their own, then add darks, then bias and flats.  Most of the time I get trippy results it's either a dodgy sub or a dodgy dark/flat.

The artifact is faintly in all subs for the Leo triplet but not in the flaming star that was in the sequence before. Never seen it before. It was in the sequence from 1am to 4am . Maybe a neighbour light but unlikely. Just one of those weird things I guess. 

[wimvb]

Can it be dew? Just wondering since it showed up after a certain time.

[Anthonyexmouth]

3 minutes ago, wimvb said:

Can it be dew? Just wondering since it showed up after a certain time.

Maybe I guess. Pretty well setup for dew bands and just leave them on all the time.