Attached Link: http://www.amazon.com/exec/obidos/ASIN/1562059548/qid%3D994961189/102-3888682-2789730
Here... I made a quick collage of different levels of lighting. The first image is the default render without any additional light (only sunlight). Of course, it is very dark because they are in a cave and because of the contrast induced by the volumetric atmosphere. The middle image only has 3 lights (one close to the face of the young and mature characters, the 3rd above her stomach). The 3rd picture has 7 lights - additional lights were places next to the face of the old woman, behind and in front of the dress of the mature woman and at the knees of the young one. You can compare the improvement. I also added a link to a reference to the book I was talking about.
