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Digital Cameras Essay, Research Paper
Digital Cameras
Written by Klyment Tan
December 17, 1996
Ever wanted a cheaper way to capture a memory or advertise in a newsletter or paper? How about having acquiring instant digital images without a scanner? If any of this applies to you, follow this article carefully. You will learn what are digital cameras, similarities and differences between digital cameras and film cameras, and their advantages and disadvantages over the film camera. Digital Cameras: loss of control or flash of the future?
What are digital cameras? Digital cameras as cameras that use CCD’s (charged couple devices) to change light into electric signals. The more light that a CCD gets, the more electricity. The CCD is a chip with many resisters on the surface. Using a shutter and a lense like a film camera, digital cameras store images on digital storage media instead of on film.
The specifications of entry level digital cameras (digital cameras around USD1000 or less) are very limited. They have a film ISO(film speed rating) of about 80-100. This speed is very slow therefore a flash is needed indoors or in lower light conditions all of the time. The average resolution of a picture is about 480×600 or a 300, 000 pixels.
Professional digital cameras, on the other hand, are very impressive. They have the features of a single lens reflex camera, or SLR. This gives a lot of control. The average resolution of images are about 3, 000, 000 pixels, quite similar to the resolution of film which is 18, 000, 000 pixels. Although the image quality is acceptable at a normal size, when enlarged, rough edges start to show up. The ISO equivalent is about ISO 800. This speed is very fast even for indoor light conditions. Unfortunately, there is a price to pay for all of this performance. Unless you are a serious and wealthy commercial photographer, USD 36, 000 is still a very heavy blow to your bank account.
There are advantages of entry level digital cameras. For one thing, processing is cheap and fast. Processing takes at least and hour for film and costs about 3-4 dollars. This is excluding film. The processing of digital camera images takes around 20 minutes depending the speed of the communications port and the computer. There is no cost for film. Also, when images are needed on computer, you don’t need to scan your images in. The images are already in digital format. This is very useful for real estate agents, newsletter photographers, Internet photos, advertising, insurance, and newspaper photographers because the resolution of the images is not a big issue in these applications.
If you are willing to pay the price for professional digital cameras, you will not be disappointed. The image quality of professional digital photos meets the requirements for pictures. Due to the use of multiple CCD’s and merging to one image, the resolution of the images from a professional digital camera is no less than 6, 000, 000 pixels. This is about a third of the quality of normal film images. Processing of digital images is also much easier to handle and process. Removable storage media also removes limits of picture storage. Having the same camera body as off the shelf SLR’s, use of these cameras are very easy to control. The fast film speed equivalent also offers necessary speed for indoor applications that require more costly film on normal cameras. Professional photographers could benefit greatly from this new technology.
Although entry level digital cameras are much more affordable and are more practical for constant use, they still have drawbacks. Their slow film speed and low resolution take the biggest blows. The slow film speed cripples the digital camera because that with a slow film speed, distracting and annoying flashes are constantly required. The resolution of the images are too poor for most applications. There is no control for shutter speed or aperture to counter light and speed effects beyond the correction of a flash. Without interchangeable memory, the picture capacity of entry level digital cameras are greatly limited. Computer storage space is also consumed to store images.
Professional digital cameras also have drawbacks. A very big issue is cost. At a cost starting around 16, 000 USD, a great initial investment is required to reap the benefits of being digital. Although professional digital cameras accommodate reusable interchangeable memory, each nonvolatile RAM card costs from 300 USD and up. It can take up to three hours to upload 24 pictures to a computer, depending on the transfer rate of the camera and the computer. Each one of those pictures takes 3 megabytes of disk space which equals 72 megabytes for a whole set. An average hard disk drive has about 1, 600 megabytes, out of which an average of 300 megabytes is already being used. This brings up the problem of buying expensive new storage media. The physical size of the camera also makes it very bulky and occasionally hard to handle.
The temporary downfall of the digital camera can be summed up in one sentence: a $3 Kodak Funsaver camera have better image quality than a $36, 000 digital camera.
We can see that digital cameras are not perfect. Neither are film cameras. The film and processing is not cheap. At about $7 for 24 pictures, we can see why people are still buying digital cameras. If the images are needed in digital format, film camera pictures have to be laboriously scanned into a computer.
The birth of digital cameras does not mean the death of film. Film cameras are still much cheaper, initially. The resolution of film is still much better than an image from a digital camera. The battery power usage is much lower that digital cameras making it easier to keep shooting without replacing. Compared to removable media of professional cameras, film is still cheaper. They are light and portable and don’t require a computer on constant standby.
Now that you have seen the advantages and disadvantages of film and digital, do not take on a solid opinion. Each have their own benefits, different applications can benefit from one of the two main kinds of cameras. As said before, entry level digital cameras are most practical from high use applications where resolution is not a big issue. Professional digital cameras are probably most practical for a professional photographer who need instantly processed images cheaply and on a computer. Film allows more unspecialized people like the common shutter bug or family member who wants to store good memories.
To conclude this presentation, digital cameras will become as cheap and as good as film cameras are right now. The keyword is eventually. Digital cameras still have a long way to go before they can seriously rival film.