Black washed (see below):
Vallejo Game Colour Stone Grey, highlighted with Vallejo Game Colour Wolf Grey, Vallejo Game Colour Bone White and Humbrol Acrylic (170) Satin White (see below):
Same colour combination from a different angle (see below):
Application of a burnt umber "dipping wash" after full immersion (IMHO too heavy) and left to dry (see below):
Retouch with Humbrol Acrylic (170) Satin White (see below):
Hmm, it was an experiment and the attraction of the Sci-Fi is that there are not hundreds of figures to paint, but methinks perhaps I spent too much time on this one and I could be a lot cruder.
Your thoughts appreciated ;)