[bojan]

To give you an example, have a look at those two images. The second one is made from RAW file, the first one is a stack from 15 exposures, 45 sec (on eq mount) with 135mm lens (Tair-11A), stacked in DSS and processed with DPP.
The LP in Melbourne is pretty terrible, as it is visible on the unprocessed image.
If you are interested in how exactly the image is processed, I can post my method, it is pretty straight forward.

EDIT:
I played a bit with DPP on your image, the result is also here. Not much better than what you have done... I only managed to stretch it a bit more, but the colour balance is similar