The Basics of Photography

Photography is a form of art where the medium is light (hence the name, photography, or writing with light.) The paintbrush is the camera and lens, and the film or other capturing device is the canvas. There are six fundamental thing needed to make an image. They are: 1) the light source/subject, 2) a lens, 3) shutter,4) diaphragm, 5) a viewfinder, and 6) a focal plane. In this article, we will discuss the effect each one of these has on photography.

A light source and subject is the first thing you need to make a photograph. After all, why would you want to take a picture of a vat of nothingness? There are many ways to light a subject, but all depend on light reflecting off of the subject. This reflected light then travels away from the subject and some of it is in the direction of your lens.

A lens is basically a piece of glass (or plastic) that bends (refracts) light so that it can be formed into an image. The lens is the most important part of a camera. Almost any of the other parts could be changed into something totally different, but the lens will stay fundamentally the same (unless you want to talk about pinholes, but they're too uncommonly used to be worth it.)

The shutter allows you to control when and for how long the light reaches the focal plane. There are three main types of shutters. 1)The blade shutter, 2)focal-plane shutter, and 3) a lens cap. the blade shutter is actually the lens and consists of blades that open and close at the press of the shutter release button. This form of shutter is sometimes combined with the aperture. A foal plane shutter is the most commonly used shutter slr (single lens reflex) cameras. As its name implies, this type of shutter is right in front of he focal-plane and can be made out of cloth curtains or metal blades. The last type of shutter is not really a shutter at all, but a lens cap. When you want to take a picture, you remove the cap and expose the film for the needed time. This form is very uncommon (for obvious reasons.)

The diaphragm, or aperture controls the amount of light that reaches the focal plane. It also control the depth of field (dof) that is in the picture. Dof is how much of the picture at what distances will be sharp. The diaphragm is made out of metal blades and is located in the middle of the lens. It stays at maximum size until before the picture is taken and then it gets smaller when you press the button.

The viewfinder is what you look through to see what the picture is going to look like. The simplest viewfinder is just a rectangular frame that gives a rough indication of the image. This type of viewfinder, along with the viewfinders on point-and-shoot and range finder cameras, is not in the same place as the lens and therefore have the problem of parallax error, where the image seen in the viewfinder isn't quite what is recorded on film. This is solved with the slr camera because the viewfinder sees directly through the lens and dose not have that problem.

The focal plane is the last essential element for a photograph. The focal plane is located behind the shutter where all the light from the lens converges to make sharp image. The film or imaging device is located here where it captures the image, completing the first stage of a real photograph!