A newbie question ... but in the attached image (quick stretch of stack, so please excuse the rubbish quality!!) of a portion of M42 (trying to build a mosaic), there's a strong halo down the left hand side. Presumably from something like Alnitak (though quite a way away)??
Do other people get such effects? Is this due to some atmospheric peculiarity, as it wasn't visible in the same area in an overlapping image taken another night?
Anything I can do to mitigate? (Just simply Photoshopped it out in the mosaic so far!
http://astrob.in/232769/0/)
Paul
P.S. Was present in all frames across a 4 hour period, so wasn't some local light source.
P.P.S. And that bright patch in the top right is a concern too! Though I should handle one issue at a time I guess
