sometimes, mostly during colder conditions when I process NEF file from my camera there is output jpeg with specific pattern (enhanced to better imagination): http://www.imagebam.com/image/e9092d438689675
. I don´t know, if it is a software problem or sensor issue.
I take this photo with Tamron 17-50/ f2.8, 20s exposure, ISO 1600. For conversion I use Adobe Camera raw 9.1
Did it occur to anyone else?
So don't worry about the pattern, go learn settings.
PS, you will never get good stars with so much light pollution in the picture so decide what it is you want to see and either go to a dark area for stars or forget about seeing many and expose for the rest of the picture.
@grofmathias: Please use Flickr to host images on NR for safety reasons.
As regards the dark sky problem, well, you will have to go for a darker exposure and see how it goes, just don't under expose and brighten too much or you will get a lot of noise. There is an old maxim - 'get it right in camera' - it still applies in that if you have to push or pull your images when editing, you will get problems. I prefer to live my life in an 'aim close, miss close' kind of way so had never encountered such a problem before.
Hope this all helped.