Wednesday, March 26, 2014

A is for Aperture

Today in the ABCs of Photography:

A is for Aperture

Aperture (ˈap-ə(r)-ˌchr, -chər, -ˌtyr, -ˌtr\): Opening that controls the amount of light that passes through a lens (such as a camera lens) 

Iris blades opening and closing. Source
The aperture is one of the most basic aspects in learning about your camera. The aperture, or f/stop, is just one of the ways you can control the exposure of your photo. As you can see on the right, we have an aperture opening and closing. The size of the hole determines the amount of light allowed to hit either the sensor of your camera, or the film; the bigger the whole, the brighter the photograph. Traditionally, f/stops range from f/2.8 to f/22, but as photography becomes more advanced, we often see f/1.2 all the way up to f/64. It all depends on what lens you are using. There is even a set of lenses, created by Carl Zeiss and commissioned by NASA, that reach f/.7! Now that's wide. 

So, why adjust aperture instead of shutter? Well, aperture controls your depth-of-field: 
  • You'll want a very large aperture, like f/2.8, to give your photograph a very sharp subject and blurry background.  You may want a larger aperture when shooting portraits, food, nature close-ups, etc.
  • You'll want a very small aperture, like f/22, for a generally sharp scene. You may want a smaller aperture when shooting landscapes, architecture, large groups of people, etc.
To learn more about controlling your exposure, check out our blog posts on shutter, overexposure and underexposure. And, stay tuned for more photography tips and tools.