Thanks! Stone, I think your question breaks down into two parts: sharpness and light distribution / shadow. The depth-of-focus of the Dallmeyer 3B shot wide open (~f3.5) is probably only about 2 inches, if that, at this at this distance. I tried to focus on her eyes. Past her chin, things fall out of the DOF. (Plus, my camera is showing some wear as the front standard is sagging a bit due to weight of big lenses) As to the light/shadow, (a) there is some (not much) fall-off on the lens. Also, (b) the dynamic range of collodion seems to be quite a bit more narrow than traditional film. Stated differently, shadows get darker much more quickly than they would with film. Finally, (c) I use KCN as a fixer. One difference between KCN and regular fix is that it also acts as a reducer. As a reducer, it will attack/reduce the shadows (at least perceptibly so) before the highlights. So you can basically reduce shadow areas (very bluntly). Having shot a few plates with full body I tried one cropped-in. And I saw this image coming together for a nice dramatic effect and we shot a number of plates trying to nail the exposure/development. A number of the plates went too far (the face just got too dark) but this one seemed, finally, to hit the mark. Below is another that kinda worked, although you can see I flubbed the focus (she prefer the one below -- me the one above). I'm excited to start using the Chamonix with gears, as I think it will be much easier to nail the focus (sliding wood leaves something to be desired).
http://farm9.staticflickr.com/8389/8...aa559208_c.jpg