APERTURE PRIORITY VERSUS SHUTTER PRIORITY

APERTURE PRIORITY VERSUS SHUTTER PRIORITY - In photography, the balance of two factors achieves correct exposure. Those two factors are aperture size and shutter speed. Aperture size, simply put, refers to the size of the hole that allows light to pass through the camera lens to the sensor or film plane. Shutter speed, on the other hand, simply refers to the length of time the hole remains open. These two factors are reciprocal. This means that the wider the aperture (the larger the hole), the less time the shutter must remain open to achieve proper exposure. Conversely, the longer the shutter remains open, the smaller the aperture (the hole) will need to be to achieve proper exposure. So now that we understand these terms, what are aperture priority mode and shutter priority mode? In aperture priority, you get to choose the aperture size while the camera chooses the proper shutter speed to achieve correct exposure. With shutter priority, you choose the shutter speed while the camera chooses the appropriate aperture size. In other words, unlike auto, where the camera retains complete control or manual metering, where you control both the aperture size and shutter speed, priority modes allow you to control either the aperture size or shutter speed while the camera controls the other factor. Since aperture size controls depth of field, you will usually choose aperture priority when you want to control the depth of focus in an image. You would choose shutter priority when your prime concern is to control camera shake or when you want to be able to stop action or to introduce motion blur. You set the priority, and the camera sets the balance in order to achieve proper exposure of the image. LARRY ELKINS - ELKINSPHOTOS FINE ART PHOTOGRAPHY