- Horizontal lines - these give breadth to a photograph and there is also implied strength and stability;
- Vertical lines - these naturally provide height, but there is also implicit strength and power;
- Diagonal lines - these provide strong dynamics and tension. Through this tension there is drama;
- Curved lines - like diagonals, these provide movement, however instead of the direct movement associated with diagonals, these are more graceful and smooth and could suggest relaxation.
The purpose of all of these is to endeavour to convey a story to the viewer, by leading him, using these methods in the direction where you consider the focus of the photograph exists. Of all of these implied lines, I consider those constructed as a result of where an individual is looking to be the most powerful. This is so as we have a natural affinity to a person's eyes, or that person's line of sight.
Taking an example, using one of my favourite photographs by Robert Doisneau - Fox Terrier on the Pont des Arts. This is a rather curious title as the dog, though in the photograph has really very little to do with the photograph. There is a great number of questions about the artist, the nude he appears to be painting and the extension of the nude in the painting through to the foot which can be seen just past the artist's left knee. All of this is very important to the construct, but for me, the highlight is the man with the dog and the lines down which he is looking. We cannot see his eyes, but these lines, or his line of sight, are constructed by interpreting the angle of body and the position of his head. The big question is, is he simply trying to see the painting on the easel, or is he trying to look around the easel at the nude woman (perhaps) on the bench. A copy of this photograph can be seen here.