While there are different reasons to take control of your lens' aperture, the most common reason to control your aperture is to affect the depth of field. Depth of field (DOF) refers to how much of your image appears sharp or in focus. Controlling DOF allows you to make background or foreground elements appear blurry to focus attention on your subject like this:
Most people are fond of the above affect, particularly for portraits. However, there are also times when you might want as much in focus as possible, like this:
Controlling aperture gives you the most direct control over DOF. Observe the differences in the following images.
This gives you a taste of what you can do with aperture. Will explore it more and talk about how to control it over the next few days.
