Gadget Savvy: Cameras Quiz

The third element is chemical -- cameras use a chemical process to capture an image on film.

The lens collects the light reflected off an object and redirects it into the camera to form a real image.

Manual-single-lens-reflex (SLR) cameras capture images exactly the way a photographer sees them through the camera.

Chromatic aberration refers to the way different colors of light bend when passing through a lens. Each color represents a different wavelength of light. A chromatic aberration can produce images in which the colors don't line up properly.

We get the word "camera" from the Latin phrase "camera obscura," which means "dark room."

The focal length is the distance between a camera's lens and the film inside the camera when the camera is focused on a subject an infinite distance away. To focus on a distant image, the camera must increase the length between the lens and the film. That's why telephoto lenses are so long.

Photographic film undergoes a chemical reaction once exposed to light. That's why if you accidentally open a camera before you finish a roll of film you'll end up with several ruined photographs.

The aperture is the opening behind the lens that allows light to pass through the camera and hit exposed film. A smaller aperture allows less light to pass through than a larger aperture. Many cameras allow photographers to adjust the aperture's size in order to adjust for different light levels.

The camera's shutter speed determines how long film is exposed to light. A long shutter speed is best for subjects that aren't moving or for time-lapse photos. Short shutter speeds are necessary for high speed photography.

A pinhole camera can be as simple as a box with a small hole on one side and photographic paper on the other side. They are easy to make and use, though they require long exposures because only a small amount of light can pass through the hole.