Since its invention over a hundred years ago, photography has totally transformed how we perceive our world. It wouldn’t be an exaggeration to say that the camera is one of the most important inventions in all human history. Photography has made it possible for humans to “see” objects that are actually thousands of kilometers away.
At their most basic level, Cameras, both the Single Lens Reflex Camera and Digital Camera simply involve using a curved piece of glass or plastic (lens) to conduct a beam of light bouncing off an object, and to redirect this light in such a way that a real image is formed-an image that looks exactly like the object in front of the lens. The only difference between manual or conventional film cameras and digital cameras lies in how these basic processes are accomplished.
In film cameras, after the lens has formed an image of the object, the image is then focused on and recorded by a chemically-coated piece of plastic, the film. Then the film is chemically processed, after which the image is printed onto a photographic paper, and then we have pictures that can then be stored in our photo album or distributed to friends as desired. But digital cameras take a shorter route to achieve the same result stated above.
How Digital Cameras Work
Digital cameras are a part of a larger breakthrough that we’ve witnessed in consumer electronics over the past twenty years-the wholesale conversion of analog information into digital information. When we really get down to it, CDs, HDTV, DVDs, MP3s, DVR, etc are all built around the principle of converting fluctuating waves into bits of ones and zeros. Conventional cameras depend fully on chemical and mechanical processes-you can actually operate them without electricity! But the digital camera presents a paradigm shift here: it has a built-in computer that records images electronically, and must thus be powered by electricity.
Just like manual cameras, digital cameras also mirrorless camera cheap use the lens-actually series of lenses-to focus the light from an object to form an image. But unlike the manual camera, the image formed by the lens in a digital camera is not focused onto a piece of film to be recorded. Instead, the image is focused onto a semiconductor device that is capable of recording light electronically. A computer is then used to break down this electronically-recorded information into digital bits of data. Let’s now take a closer look into the inner workings of a digital camera.
Included in a digital camera’s built-in computer is a sensor that converts light into electrons, or electrical charges. Depending on the camera’s manufacturer, this image sensor may be either a Charge Coupled Device, (CCD), or Complementary Metal Oxide Semiconductor (CMOS). To be honest, notable differences exist between these two types of sensors (i.e. CCD and CMOS). But they perform the same basic function in a digital camera-converting light into electricity. Hence, for the purpose of understanding how a digital camera works, we’re going to think of them as identical devices.
And somewhat like the film cameras, a digital camera also has to control the amount of light that reaches the sensor. Yes, it also makes use of the Aperture and Shutter Speed. But these are mostly automatic and can be reset electronically. Now, a digital image is just a long string of 0s and 1s. It is the sensor that reads and interprets the values of these digits as contained in the cells of each recorded image.