That was ps, there is one similar to the original in this album, but in fact the original was a bit green (i used another setting). So i ps the picture a "little" bit. I wanted it purple indeed, not natural, only as experience to see how it would be. :-)
There are others (zoomed pictures from horizons) that i photoshoped a tiny bit too, only adjustment of levels, because the landscape far away was foggy (polution, blergh).