Here is an alternate lighting version of the Afghan Girl image that I posted before. This was done just by shifting the light settings in the already rendered image in Lux Render. This is the real power of a physically based and unbiased rendering engine. Since everything is just calculated in numbers changing these options are trivial. In this one I reversed the fill and key lights (lighting stronger on the fill, and lesser on the key light) This one does have a little post because on the light reversal I noticed some mesh ripping on the shoulder so a quick heal brush took care of it. You can see the original image here - http://www.renderosity.com/mod/gallery/index.php?image_id=2586082