Black on black

The other day I took a photograph of a girl who was wearing black clothes. Black jacket, black T-shirt, black ski-pants. The problem is - How do you keep them looking black and bring out detail so that it doesn't look like one big blob on the picture?

OK here is the raw file as I brought it in to the editing software.

And here it is with colour balance adjusted and a default levels adjustment applied - not much difference - just a little brighter.

Now I created a new threshold adjustment layer and took the threshold value down until I just retained a solid black on the Tshirt and jeans.

Using the magic wand selector tool with feather set to 0 and the "contiguous" checkbox and "all layers" both selected, I selected the black area. I then tidied up the selection by deselecting the darkest part of the jacket on the right and reselecting a few bits on the left. At this point I deleted the threshold adjustment layer and then created a new levels adjustement layer.

I moved the middle slider down until I was plainly seeing shadows without the black clothes looking too grey.
After this, the layers were merged, the image converted to 24 bit colour depth, dust removed by cloning, resized and sharpened to give this:-