Aperture is a strange concept when learning photography. Aperture is defined as the size of the opening in the lens that light passes through before it hits the photographic medium which, these days, is an electronic sensor at the back of the camera. Aperture is also measured in some strange language called f-stops. F-stop numbers look to defy logic as the larger they are, the smaller the size of the aperture and the larger the focus area. Consequently, the smaller the f-stop number, the larger the size of the aperture and the smaller the focus area. Confused?
Recently, Karen of Karma’s When I Feel Like It Blog, came up with what she calls a little mantra about aperture so she can remember what the f-stop numbers mean. I found the mantra brilliantly simple. You know, one of those “I could have had a V-8″ slap to the forehead brilliant. Here it is:
Big number, big focus area, little number, little focus area.
Let’s take this mantra out for a test drive. Below are two photos which demonstrate Karen’s mantra.
Notice everything is in focus from the flowers all the way back to the mural, a big focus area.
The classic selective focus effect by using a lens wide open at its smallest f-stop number and small focus area. Notice the change in the shutter speeds and ISO between the two photos to maintain the correct exposure.
Next time you get confused about aperture, remember Karen’s mantra, “Big number, big focus area, small number, small focus area.” Thanks, Karen.
The mural of the firefighters in the photos is found on the side of the Cicero Volunteer Fire Department firehouse in Cicero, New York. The photo below will give you a better idea of the distance between the flowers and the mural.