Understanding Aperture in a Digital Camera

Basically, the aperture controls the amount of light into the camera. It may be enlarged or contracted.

The size are measured on a scale called "f-stops." A f/2.8 is larger than a f/22 - the smaller the number, the larger the aperture. Most common f-stop settings are: f/2.8, f/4, f/5.6, f/8, f/11 and f/16. Also, each f-stop is about half as large as the previous one. In other words, f/2.8 allows about twice as much light as the f/4 settings.

Changing your aperture size will not only control the amount of light going into your camera; it can also change the focus of your foreground and background. This area of focusing is called "depth of field."

Larger apertures give a shallow depth of field. In a shallow depth of field, your subject or part of your subject will be in sharp focus. On the other side, smaller apertures give a larger depth of field. That's when most part, if not all, around the subject will be in sharp focus.

Skillful photographers can manipulate the depth of field to emphasize certain details of the pictures and down play other details. With a large aperture, you can focus your subject and blur the background. With a smaller aperture, you can have both your subject and background show up sharply focused in the picture.

If you play enough with it, you can even keep the subject in sharp focus while blurring the foreground and background of the subject.

Try it and see how that works.

David