Just had another look at the comparison gallery:
https://plus.google.com/photos/109609428403596349302/albums/6044645069501365185/6044645222210889458?pid=6044645222210889458&oid=109609428403596349302
I noticed that the middle "tile" beneath Vader was darker in the gout.
May have been discussed before, if so I apologize :P