The SLR camera offers many advantages for focus and exposure control.
The single-lens reflex camera (SLR) is the camera of choice for many photographers who wish to move beyond the amateur level of photography. It is more portable than large format cameras yet has superior focusing abilities over point-and-shoots. Depending on what subjects and under what conditions you wish to photograph, certain key characteristics of an SLR may be to your advantage.
Close-Up Images
SLRs are an improvement over point-and-shoots when creating images up close to a subject. The viewfinder of the point-and-shoot camera is located off to one side and does not match the angle of view that the camera's lens captures. This results in what is known as "parallax error:" when the composition of a close-up image does not match what is seen in the viewfinder. An SLR camera eliminates this problem with its mirrors and pentaprism. A mirror at a 45-degree angle behind the lens bounces the image into a pentaprism on top of the camera body, providing an image in the viewfinder that matches exactly what the lens "sees."
Viewfinder Perspective
Because of its pentaprism, SLR cameras provide a more natural way to view compositions in the viewfinder. This is opposed to large-format cameras that contain no mirrors. These cameras require that you focus by viewing a large frosted-glass screen under a hood that blocks light. The image is projected onto the screen in the manner in which light is converted through the lens: reversed both left-to-right and top-to-bottom. An SLR's pentaprism corrects the orientation, avoiding this awkward way to compose.
Exchangeable Lenses
As opposed to point-and-shoots, the vast majority of SLRs have exchangeable lenses. This allows you to adapt to different shooting situations by using varying focal lengths of lenses. These include wide-angle lenses, normal lenses, long lenses or zoom lenses that contain all options. While many point-and-shoots offer zoom options, the optics of SLR lenses are far superior and allow for manual focusing which creates sharper images.
Faster Shutter
SLR cameras are capable of faster shutter speeds than their large-format counterparts. The SLR camera's shutter is a "focal plane" style: a curtain that moves either from left-to-right or top-to-bottom and is located in the camera body. Large-format cameras employ a "leaf" style, located in the lens and composed of a series of overlapping leaves that open in a circle from the center. A leaf shutter is more complicated in that it must open and close again to make an exposure, while a focal plane shutter makes one sweeping motion. Because of the dual motion of the leaf shutter, it is usually not capable of shutter speeds as fast as those of the SLR.
Manual Exposure Controls
A major advantage over most point-and-shoot cameras is the manual or semi-manual exposure control available with SLRs. You can choose your shutter speed to control how much motion blur or frozen action you want in an image. Aperture controls how much of the depth of the image remains in focus. SLRs allow you to control at least one of these, if not both, while most point-and-shoots do not offer these controls.
Tags: camera body, does match, exposure control, focal plane, leaf shutter
