Submitted for your approval, two crops from one image of a squirrel. He is not a particularly sinister squirrel (well in one image he is if we take a literal archaic definition of Sinister: on the left side; left)
The Squirrel is heavily side-lit with the sun coming at about a 45° degree angle-camera left. This causes the squirrel to be lit on his right and shadowed upon his left. I created two equivalent crops of this image. In the first image I placed the squirrel on the right rule of thirds. In the second crop, I placed him on the left rule of thirds. Given that background is pretty much a wash in this compositional exercise, what does the crop choice do to your image?
The top image has the light side of the squirrel inward, toward the center of the frame. The bottom image has the light side of the squirrel outward, toward the near edge of the frame. Which crop feels more natural to you? I can tell you I like the top crop a lot better than the bottom crop. The bottom squirrel appears crowded with the edge while the top squirrel feels comfortable in space. In fact, "space” is the key word here.
In the Rule of Space, we speak of space applying to the direction in which an entity is facing or ‘looking’. What is going on here? The squirrel is facing dead-on straight at us but the shadow/light of the figure is creating a de facto directional facing. The light side is perceived visually as the front and the shadow side is the back, if you will. This illusion and sensibility create a situation where our perception of the top squirrel is that he is facing into the frame and the bottom squirrel is facing out of the frame. The difference in feel is subtle to be sure but palpable.
Often, a face isn’t the sole clue as to in which direction an entity is facing or perceived to be facing. Take this into consideration as you frame and later crop your images to keep a more pleasing composition.
Rikk Flohr © 2013