M101 from Blacklands DSC

[Carole]

OK I have examined the subs from both nights and the "luminosity" appears on both nights, so it's not the lightning.  It doesn't appear in the M31 image so it's not a permanent feature (same set up not moved).

When really overstretched it appears as an arc right through the image and the only thing I can think of is some sort of reflection from the neighbouring lights that the other campers were using.  In particular there was a really bit bright light in the next tent which we had to ask them to cover.  

Just look at the overstretched but otherwised unprocessed image and you can see the arc:

[JohnP]

yep thats what I could see.. Is there a bright star nearby...? Look at todays APOD....

[Carole]

I can't see anything particularly bright John, but it seems a reasonable explanation. 

Carole