This was a witch that was hanging from a brownstone on the upper east side of NYC on the day after Halloween a couple of years ago. I can't remember all of my post-processing, but my notes suggest that I applied an infrared black and white filter, and then inverted it, so it took on the appearance of a ghost. I used a black grunge texture to create a night-time effect.
This is no Casper the friendly ghost! I really like the glowing whites of the eyes, nose and mouth and the shiny black face against the grungy textures and colors of the bkgd and white fabric. I also like how you captured the vertical lines and folds in the white fabric. Would have liked to see the bottom of the ghost but maybe something was in the way. Not a big deal actually.