An aperture is a hole or an opening through which light travels. In photography, it's the hole of the lens. When you use the manual or aperture priority settings of a camera, you can adjust the size of the aperture stop (aka f-stop) to control the amount of light that enters the camera. Along with the ISO (light sensitivity of the film or digital media) and the shutter speed, aperture determines what kind of exposure you'll have. It also controls the depth of field. For example, the wider the aperture the shallower the depth of field (the blurrier the background and area around the subject), and the smaller the aperture the greater the depth of field (the sharper everything in the image appears).
... And it's the topic I chose to focus on for week five of my 365 project. Below you'll see examples of shallow depth of field, great depth of field, and everything in between. A wider aperture also brings in more light which is great for long exposures, and when shooting with back lighting, a wide aperture creates a bokeh effect (a topic for a later week in my project) and a small aperture creates the sunbursts that I like to use frequently.
Below are examples of all these effects, and to see my whole 365 project click here. See you next week!