The Aperture Setting on Your Camera
Aperture is one of the three factors that determine exposure. The aperture housing contains thin, metal plates that open and close to let light through the aperture and into the camera.
Every camera is different, so for specific instructions, such as how to change the shutter speed, refer to your camera's manual. To download a free manual, click here and enter your camera's model number, select the correct model from the drop-down list, and then click on the user manual link.
The size of the aperture is related to the amount of light. The size of the aperture is represented by a value known as the "F-Number." (Example: F3.5-5.6)
A larger aperture allows more light.
A smaller aperture allows less light.
The opening in the aperture is described as the Exposure Value (EV).
Increasing the Exposure Value (+1 EV) means the amount of light doubles.
Decreasing the Exposure Value (- EV) means the amount of light is cut in half.
Image on the left : aperture slightly open
Image on the right : aperture wide open