Just getting the tones roughly the same. Using light, realism ( to a certain extent:P ) . Around 40-60mins work :) I know some of the shapes are a little off, and it's tiny.. but it was just a practice that turned out ok-ish ^_^ ( 2nd painting EVER ... so .. yeah...)
http://img109.imageshack.us/img109/1...llzcopy3yi.jpg
SLIGHTLY less blurry version.. sorry about that =|
http://img69.imageshack.us/img69/2867/skullzcopy1ny.jpg