First Attempt - A practice run

So I decided to have a practice run before actually driving out an hour and coming back with bad images...

But anyway, I live near a somewhat light polluted area as you can see from one of the 15 shots I stacked in DSS:

IMAGE LINK: http://www.flickr.com …80072515@N06/10​566683073/

IMAGE LINK: http://www.flickr.com …80072515@N06/10​566677383/

Keeping the stars under control is a matter of using levels and curves delicately. You have also clipped the black levels which give you a cleaner looking sky.

The vignetting makes setting the black point a bit tougher.

In Photoshop...

Curves>2x click the black dropper>set the R, G and B levels to 27>then click a dark area of the image not effected by vignetting. This will bring the background color where you clicked to approximately the correct color.

Curves>click the grey dropper>click somewhere in the image that also has a dark background and no nearby stars This balances the color channels.

Due to the vignetting, you may chose to do an aggressive crop.

Then, I'd go back and forth with levels and curves. Using the midpoint slider in levels, you should darken the image. Then using curves, you should selectively brighten the other areas.

Since this is a star image, and no major features, you may just be able to use levels and not worry about curevs.

Just make sure as you stretch, that it isn't bloating stars or robbing their color.

Thanks, I did revisit my technique and managed to get these:

IMAGE LINK: http://www.flickr.com …80072515@N06/10​579170453/

IMAGE LINK: http://www.flickr.com …80072515@N06/10​578932426/

IMAGE LINK: http://www.flickr.com …80072515@N06/10​578951444/

Nice. You preserved the star color nicely. There is some data in the center of the frame, but there is also a bright spot in the center that I think is just an artifact. It's hard to stretch one and not the other.

If you choose to go further, flat frames can help even the vignetting and allow further stretching.