With one light on either side, the amount of light and the contrast depends on where she moves her head. If she moves forward it gets more dramatic, if back, the light evens out.
I really like this one, side light is less strong (did you use a reflector here? Or fill flash?) I also like the crop here, it really brings the attention to her face. The fact that it is partially hidden behind her shoulder only adds to the composition I believe.
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{K:164501} 11/6/2004