Dimension of the space
As photographers we also deal with how the space is filled within the frame.
In observing the work of many photographers I admire I am always attracted to those images in which space is well represented. It allows me to get into photography a lot more than those closed-shot images where only one thing gets thrown in your face. Photography, rather than living it, you undergo it.
When I can find a sense of depth, my eyes wander, caressing the various layers, reaching down to the bottom.