This image was first enhanced in Saturation, following which a noise reduction plug-in was applied and curves were used to increased the brightness of the low- and mid-range tones while reducing contrast in the higher levels. A new difference layer was created and a sample was taken from a region with few visible stars and applied to the difference layer. This gave a very black sky, so the difference layer was scaled back a few percent. The image was flattened and scaled to 33% to reduce the bloated stars. All processing was done in photoshop. See the previous image for the original appearance.