Whether photographers realize it directly or not, they often use geometry in the composition of their shots. One of the most basic rules taught in photography is the "rule of thirds," which should be implemented when taking pictures. The idea behind the rule of thirds is to visually break up your shot into three parts, horizontally and vertically, so that you have nine equal rectangular sections within your shot. In order to create a well-balanced and interesting photograph, position the most interesting features in your photograph along the intersections of these angles within your frame. Instructors usually recommend that photographers employ the rule of thirds when viewing their shot through the LCD window on their cameras. While it is a suggested rule, it is often OK to break if it allows for a more visually interesting shot.
When Choosing an Angle
So much about taking a successful photograph is about choosing the perfect angle to shoot the photo from. This is not only a matter of where you stand when taking the picture, it is also a matter of how the camera is held when taking the picture. In geometry, mathematicians use angles to orient the positions of matter within a plane. Similarly, photographers must use their knowledge of angles to guide their picture taking. In the case of photography, the "plane" is the composition of the photograph.
Photographers can choose to take a photo straight on with the subject, looking diagonally up, looking diagonally down, looking straight up or down, and any angle in between. While it is rare that photographers will implement a protractor to make an exact measurement of the angle the photo is shot from, a subconscious consideration of the angles is often used.
For Visual Interest
Geometry is not just used for mathematical purposes. Geometry is featured in many elements of life and society. This includes the building of bridges, architecture, design and art. This is why photographers will often use geometry for visual interest. For instance, a photographer can pose a subject in front of a series of intersecting or parallel lines. The subject will break up the intersections or block out some of the parallel lines to add visual interest. More directly, a photographer could pose a subject in a pose that resembles a polygon, or within a particular polygon.