What is Aperture in Photography?

Aperture is the physical opening of the lens

Aperture is defined as the physical opening of your lens. A large aperture lets more light into your camera than a smaller aperture would. The aperture is measured by f-stops. Larger f-stop numbers (f/16) signify a smaller physical aperture. Smaller f-stop numbers (f/2) signify larger physical aperture. F-stops and aperture size can be a little bit confusing at first, but you'll get the hang of it pretty quickly.

Large Aperture / Small f-stop (f/1.8) - Shallow Depth of Field

Asides from controlling the amount of light that enters the camera, your aperture also helps to control your depth of field. Depth of field is how much of your image is in acceptable focus. Larger physical apertures, or smaller f-stop values, gives you smaller/shallower depth of field. This means that less of your image beyond your focus area will be in focus. A smaller physical aperture, or larger f-stop value, will give you a larger/deeper depth of field. This means that a large portion beyond your focus area will be in acceptable focus. 

Small Aperture / Large f-stop (f/7.1) - Deep Depth of Field

Of course, you'll also have to take into account your shutter speed and ISO when taking a photograph.

NEXT - What is Shutter Speed in Photography?

Back to Digital Photography 101 Index