How Cameras Work

Cameras capture moments by recording light. They work in a way similar to your eyes. Light enters through a lens and is focused onto a surface that records the image. Old cameras used film to record images. Modern digital cameras use electronic sensors. But the basic idea is the same.

How Light Makes an Image

Light from a scene enters the camera through the lens. The lens bends the light and focuses it into a sharp image. The aperture controls how much light gets in, like the pupil in your eye. The shutter opens and closes quickly to let in just the right amount of light. The image is recorded on film or a digital sensor.

Digital Cameras

In a digital camera, the image falls on an electronic sensor made of millions of tiny light-detecting cells called pixels. Each pixel records the color and brightness of the light hitting it. A computer chip in the camera processes all the pixel data and creates a digital image. This image is stored on a memory card.

Fun Facts

• The first photograph ever taken was in 1826 by Joseph Nicephore Niepce. It required an eight-hour exposure.
• A modern smartphone camera has more computing power than the computers used to send astronauts to the Moon.
• Some cameras can take over 20 photos per second.

Did You Know?

The word camera comes from the Latin term camera obscura, meaning dark room. Ancient people discovered that light passing through a small hole into a dark room creates an upside-down image on the opposite wall!