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Introduction to Aperture in Digital Photography Adobe Photoshop / Photography
Digital Photography School » · Photography · September 13, 2006
Put most simply - Aperture is the size of the opening in the lens when a picture is taken. When you hit the shutter release button of your camera a hole opens up that allows your cameras image sensor to catch a glimpse of the scene you're wanting to capture. The aperture that you set impacts the size of that hole. The larger the hole the more light that gets in - the smaller the hole the less light.