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Title: How Camera Works - F Stop
Tags: camera
Blog Entry: The aperture is one of the more confusing parts of how cameras work. The aperture setting is also sometimes referred to as an f-stop. While the shutter speed affects the  duration  of light hitting the sensor, the aperture affects the  amount  of light hitting the sensor. To put it simply, the aperture is the part of a lens that dictates how much light is let through to the sensor if its wide open, lots of light gets through. If its closed down, not much light gets through. In essense, it performs the same as the pupil of an eye. If you are in a dark room, the pupil is open; sunlight, the pupil is small.  Aperture settings are expressed as decimal numbers, and work opposite to the way youd think a higher number lets in less light than a lower number. Each aperture has an Open, and a Closed the most and least light it will let in. In between it is what is known as the f-stops, or aperture settings numbers like f1.6, f2.2, f8.0, f16.0, with many in between. Different lenses can have different apertures for example, a cheaper lens may only open to f4.0, not letting in as much light as a more expensive lens that will open to f1.6.  Changes to aperture will effect " Field of Depth " as well and you should refer to this tutorial as well.  Finally, another good utilization for apature is when taking night time city scenes. Utilizing a smaller apature setting can help enhance the "star like - radiating" effect of lights, which can lead to some nice nightscape images. More info on http://www.homephotog.com/tutorials/aperture.shtml