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Hi I'm Chris Davis for About.com. Understanding the elements of exposure can be a little tricky at first so let's take a look at how it impacts your photography.

What is Exposure in Photography

Simply put, exposure is the amount of light collected by your camera in a single photograph. Too much light will result in an overexposed or washed out picture, while not enough light will produce an underexposed or dark picture. Most digital cameras have a built in light meters which creates an ideal exposure by measuring the light entering the camera.

This measurement is a value determined by the cameras aperture and shutter speed based on a predetermined ISO. These three controls, Aperture, Shutter Speed and ISO work together in creating exposure.

Aperture and Exposure

Aperture controls the size of the opening of the lens which controls the amount of light entering the camera. It can be adjusted up or down, opening or closing the aperture. The control settings are referred to as f-stops. Changing between each stop will either double or halve the amount of light depending on the direction you make the change.

Shutter Speed and Exposure

Shutter speed controls the amount of time the shutter is allowed to remain open while taking a single photograph. It is measured in seconds and fractions of seconds. The longer the shutter speed remains open the more light is allowed to enter the camera.

ISO and Exposure

ISO controls the sensitivity of the digital cameras sensor to light. ISO settings range from 100 to 3200 or more on some cameras. The higher the ISO number the more the cameras sensor will be sensitive or add light to an image.

With practice you will get it. To learn more check us out on the web at About.com. Thanks for watching.
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