ISO, Aperture, and Shutter Speed: Review

ISO (Sensitivity)

Aperture (F-Stop)

Aperture controls HOW MUCH light is allowed into the camera through the lens. It is similar to your eye squinting. When you squint things become sharper, but when you open your eyes all the way you get better light.

The lower the f-stop or aperture, the more light that is being allowed in. The higher the f-stop or aperture the less light that is being let in.

Aperture can have dramatic affects on your photographs beside the amount of light. Aperture has a large effect on the depth-of-field (area of focus). The higher the aperture the greater the depth of field (more of your photograph will be in focus). The lower the aperture the smaller the depth of field (lessarea in focus).

When photographers talk about “closing down” or “opening up” they are referring to changing the aperture. Closing down means to let less light into the camera, and opening up means letting more light into the camera.

Shutter Speed

Shutter speed controls HOW LONG light is allowed to hit the camera sensor. Shutter speeds are a fraction of a second. A shutter speed of 60 is actually 1/60 of a second.