When it comes to creating compelling photographs, there are usually a number of factors at play—subject matter, location, composition, light. But there are two constants that will play a role in every image you take: motion and depth of field.
We know that shutter speed controls the length of time that light is allowed to hit the camera’s sensor, but what we haven’t talked about is how it also controls how we capture motion within an image. The less time that light has to enter the camera, the less time your subjects have to move around and become blurry. This lets you do things like freezing the motion of objects (Figure 2.9) or allowing the motion to become part of your image (Figure 2.10).