Digital Cameras Versus Film Cameras: Do You Know the Difference?
Since its invention more than a hundred years ago, photography has totally transformed the way we perceive our world. It would not be an exaggeration to say that the camera is one of the most important inventions in the entire history of mankind. Photography has made it possible for humans to “see” objects that are actually thousands of miles away.
At their most basic level, cameras, both single lens reflex camera and digital camera, simply involve using a curved piece of glass or plastic (lens) to drive a beam of light that bounces off an object and redirects 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 is in how these basic processes are carried out.
In film cameras, once the lens has formed an image of the object, the image is focused and recorded by a chemically coated piece of plastic, the film. Then the film is chemically processed, after which the image is printed on a photo paper, and then we have images 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 mentioned above.
How Digital Cameras Work
Digital cameras are part of a great advance that we have witnessed in consumer electronics for the past twenty years: the bulk conversion of analog information into digital information. When we really get down to business, CDs, HDTV, DVD, MP3, DVR, etc. they are based on the principle of converting fluctuating waves into bits of ones and zeros. Conventional cameras are completely dependent on chemical and mechanical processes; You can operate them without electricity! But the digital camera presents a paradigm shift here: it has a built-in computer that records images electronically and therefore must be powered by electricity.
Like manual cameras, digital cameras also use the lens, actually a series of lenses, to focus light on an object and form an image. But unlike the manual camera, the image formed by the lens in a digital camera is not focused on a piece of film for recording. Instead, the image is focused on a semiconductor device that is capable of electronically registering light. A computer is then used to break down this electronically recorded information into digital bits of data. Let’s now take a closer look at the inner workings of a digital camera.
A sensor is included in the built-in computer of a digital camera that converts light into electrons or electrical charges. Depending on the camera manufacturer, this image sensor can be a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). To be honest, there are noticeable differences 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. Therefore, in order to understand how a digital camera works, we will consider them identical devices.
And somewhat like film cameras, a digital camera also has to control the amount of light that hits the sensor. Yes, it also uses aperture and shutter speed. But these are mostly automatic and can be reset electronically. Now, a digital image is just a long string of 0 and 1. It is the sensor that reads and interprets the values of these digits contained in the cells of each recorded image.
Then another device known as an analog-to-digital converter (ADC) converts each recorded light pattern (pixel values) into a digital value by measuring the amount of charge in each cell and converting that measurement into binary form. Remember we said earlier that every digital camera has a built-in computer? Now a processor there interpolates the data from the different pixels to form a natural color. For most LCD-equipped digital cameras, at this stage it is possible to view the image that has just been photographed before deciding to print it.
At this stage, the information is stored in some kind of memory inside the camera; All digital cameras are equipped with various storage systems, most of them removable storage devices. We can consider them as forms of reusable digital film. And because images take up a lot of storage space, most digital cameras use some form of data compression to reduce file sizes. A card reader can then be used to transfer the information stored therein (ie, photographic images) to a computer for later use.
The processes described above surely sound complicated, right? Do not worry. In practice, everything happens so easily that we hardly take notice of anything while using a digital camera, which is what makes it fun to use: the ease and the speed. Suppose you want to email a photo to a friend. With conventional cameras, you will first have to capture the image, process the film, print the image, and then use a scanner to capture the image again and record it as pixel values to email to your loved one. But with a digital camera, the image is automatically divided and recorded as pixels ready to be emailed. That is the fun. In addition, you can also view the image, live, before setting up printing.
Therefore, despite the comparatively better quality of movies, digital cameras will continue to gain popularity. Also, as digital imaging technology continues to improve by leaps and bounds, it would be interesting to see what happens to the conventional film camera.
Author: Kenneth Agwu