HOW DOES A CAMERA WORKS

A camera lens collects and focuses the light — but how is that information recorded? Historically, photographers were also chemists of sorts. Film is made up of light sensitive materials. When those materials are hit with light from the lens, they captured the shape of the objects and details like how much light is coming off of them. In the dark room, the film that was exposed to the light is again put in a series of chemical baths to eventually create the image.

So then how do digital cameras work? While the lenses, techniques and terms are the same, a digital camera’s sensor more closely resembles a solar panel than a strip of film. Each sensor is divided up into millions of red, green and blue pixels (i.e. megapixels). When light hits the pixel, the sensor converts it into energy and a computer built inside of the camera reads just how much energy is being produced.

Measuring how much energy each pixel has allows the sensor to determine what areas of the image are light and dark. And since each pixel has a color value, the camera’s computer is able to estimate the colors in the scene by looking at what other nearby pixels registered. Putting the information from all the pixels together, the computer is able to approximate the shapes and colors in the scene.

If each pixel is gathering light information, then camera sensors with more megapixels are able to capture more detail. That’s why manufacturers often advertise a camera’s megapixels. While that’s true to some extent, the size of the sensor is also important. Larger sensors will gather more light, making them better performers for low light scenes. Packing lots of megapixels into a small sensor actually makes the image quality worse, because those individual pixels are too small.