Theory of Light and Shade

The context of this image is that a skeleton model was set up in front of a spotlight, with it's shadow cast up and onto the wall behind it.

The use of planning lines becomes evident, and well used in the shoulders, where one shoulder is pushed behind from the angle of projection.

Once again, messy lines impact onto this picture, especially in the spine, where the shoulder blade just appears as a weird notch in the backbone. The lower end of the picture appears to be wider than the rest, but unsupported by foreshortening, and so appeared simply as a bad perspective.