Cameras have changed dramatically over the past centuries and these days almost everyone has one on their phone. On Instagram (an image sharing social media site) there are 95 million posts every day, 500 million people using Stories every day and over a billion monthly users [March 2019]. Cameras and photographs are a major part of people’s lives, but do you know how cameras work?

Taking A Picture

When you press the button to take a photograph, multiple things happen. An aperture opens (a hole) in the lens which allows light to pass into the camera. The light is focused by the glass in the lens and it then hits the sensors in the camera. This is very similar to the human eye with the pupil(aperture),cornea and lens(lens) and the retina(sensors).


When the light hits the sensors it is broken up into millions of pixels. Pixels are what you find on your TV or phone screen. Each pixel has a colour and when there are lots of them, the human eye can’t distinguish each individual pixel and so they merge together. Each pixel value is translated into a voltage which is then sent off to be stored and later turned into an image. 

An image showing zoom to see the pixels

More Enigmas
Electromagnetic Spectrum