Thank you Alejandro! I have to say that it is not that difficult to reveal if you get the data on the nice dark site. This one was taken in Causse Noir, 30 km east from Millau in southern France. This is one of the places where photos comparable to cooled CCD can be achieved with DSLR. But of course, there was a lot of fiddling with histogram and gradients, color saturation etc. Honestly- this result would not be possible without Pixinsight. Recently I have found old data of Rosette nebula, which I gave up (gradients, noise, short exposures), and thanks to Pixinsight I got decent results...
To conclude- dark skies is the primary condition, and the second is good processing tool..