![Picture](/uploads/1/1/2/6/11261556/1371337661.jpg)
As an experiment, I mixed silver in with the black I was using and drybrushed the cape. The color and texture looked nice, but the contrast between fold and crease was insufficient. I took some pure black and painted inside the creases, which were easier to see at this point because of the drybrushing (the contrast was unsatisfactory as a final product but a useful as a guide). Of course the black slopped over a bit; the next step was to add even more silver to the mix and paint just the high points. I did another iteration of painting folds and creases to create some decent shadows.
The image on the left was made after the last iteration, but before I cleaned up the edges. I painted the silvery-black over most of the deep-black to make straighter edges. The only problem now is when admiring my work, I can't see if the shadows are painted on or just the natural effect of the lighting!