Compared to most artistic mediums, photography is fairly new. The first permanent photograph was produced in 1826 by Joseph Nicephore Niepce. Niepce produced his photos on polished pewter plates covered with a petroleum derivative dissolved in white petroleum.
We’ve come a long way since then, from digital cameras to Instagram to personalized photo books, all to capture those unforgettable moments. Let’s take a look at the basics of how a traditional SLR camera operates.
The Three Elements
A film camera consists of three basic elements: an optical element (the lens), a chemical element (the film), and the mechanical element (the camera itself). Combining these three elements is the key to a crisp image for those custom gifts.
The Lens and Focus
A lens is, at its simplest, a curved piece of glass or clear plastic. The lens takes the beams of light bouncing off objects and redirects them to combine and form an image. The nature of this image depends on the structure of the lens and the angle that the light beams enter the lens.
While you can’t necessarily change the structure of the lens, you can adjust the angle of entry. The angle of light entry changes as you move the object closer or farther away from the lens. You can accomplish this by physical moving yourself closer or farther away from the object, but the focus does the exact same thing. As you turn the focus of the camera, you’re moving the lens farther or closer from the surface of the film.
When you expose a film to an image, it essentially makes a chemical record of the light patterns using tiny, light-sensitive grains spread into a chemical suspension on a strip of plastic.
Once you’ve finished a roll of film, it is exposed to a series of other chemicals that react with the light-sensitive grains. For black and white film, the chemicals darken the grains, producing a negative where the darker areas appear lighter and the lighter areas appear darker. When the photos are printed for wall decorating, they are converted to positive images.
Color film has three layers of light-sensitive materials that respond to blue, red, and green. These layers are exposed to chemicals that dye the layers of film, producing a full-color negative.
The Camera Body
A good image is all about controlling the light. If you were to place some film on the ground and focus an image onto it with a lens, you wouldn’t get anything usable. This is where the camera body comes into play. A camera is essentially a sealed box with a shutter, which opens and closes between the film and lens, allowing a brief moment of light to pass through the lens and camera body onto the film.