SLR camera operation
1333 Single Lens Reflector (SLR) Camera

There are two types of consumer film cameras on the market –– SLR cameras and "point–and–shoot" cameras. The main difference is how the photographer sees the scene. In a point–and–shoot camera, the viewfinder is a simple window through the body of the camera. You don’t see the real image formed by the camera lens, but you get a rough idea of what is in view.

In an SLR camera, you see the actual real image that the film will see. If you take the lens off of an SLR camera and look inside, you’ll see how this works. The camera has a slanted mirror positioned between the shutter and the lens, with a piece of translucent glass and a prism positioned above it. This configuration works like a periscope – the real image bounces off the lower mirror onto the translucent glass, which serves as a projection screen. The prism’s job is to flip the image in the screen, so it appears right side up again, and redirect it onto the viewfinder window.

point_shoot_camera Compact Camera A point-and-shoot camera, also called a compact camera, is a still camera designed primarily for simple operation. Most of these cameras use focus free lenses or auto focus for focusing, these cameras have automatic systems for setting the exposure options, and have flash units built in. These cameras are popular with people who don’t consider themselves photographers but want an easy to use camera for vacations, parties, reunions and other events.

When you click the shutter button, the camera quickly switches the mirror out of the way, so the image is directed at the exposed film. The mirror is connected to the shutter timer system, so it stays open as long as the shutter is open. This is why the viewfinder is suddenly blacked out when you take a picture. In this sort of camera, the mirror and the translucent screen are set up so they present the real image exactly as it will appear on the film. The advantage of this design is that you can adjust the focus and compose the scene to get exactly the picture you want. For this reason, professional photographers typically use SLR cameras.