Traditional cameras work by exposing a piece of film (celluloid covered with a light-sensitive emulsion, such as silver nitrate) to light for a fixed amount of time. The film reacts to the light that passes through the camera's lens, "capturing" reflected images.
The biggest advantage of traditional photography is that, depending on the equipment and conditions, a photograph can have almost infinite resolution. That is, its quality is not limited by the finite number of "dots" that comprise the image.
Traditional photography also has some drawbacks. Film must be processed before the results can be seen. Great care must be taken to preserve the negative image produced on the film. It can be extremely difficult to modify a film-based photograph, using traditional processing methods. Finally, film processing and printing can be a slow, expensive process.
And the New Way
Instead of using only a lens to capture light, most digital cameras use a charge-coupled device (CCD) to convert light into a digital image. CCDs are commonly used on scanners and video cameras as well as digital cameras.
After capturing an image, a digital camera stores it in a special type of memory or on a magnetic disk. Manufacturers have developed a variety of storage technologies. Some cameras use a standard 3.5-inch floppy disk for storage. Other cameras use PC Cards or special "memory sticks" to hold photos; these devices use flash memory to store data even when the camera is turned off.
Digital cameras can store photos in a variety of formats, which may require different amounts of storage and provide varying resolutions. Most digital cameras can store images in high-resolution JPEG or TIFF formats, but these formats consume a great deal of storage space.
The biggest advantage of digital photography is convenience. Many cameras provide LCD screens so you can review a picture right after taking it. This lets you decide whether you want to keep or delete the picture. Instead of taking film to a developing lab, you can copy the images to a PC and print them out.
Printing is both the biggest blessing and biggest curse of digital photography. Even though digital cameras store pictures at very high resolutions (millions of pixels per image), the printed image's quality is restricted to the printer's quality. So, if you use a color ink jet printer with a resolution of 300 x 600 dpi, that's as good as your images will look. For best results when printing digital photographs, use premium-quality photo printing paper, which is available at any office supply store.
You can use color laser printers for higher-resolution printing, but they are very expensive. A less expensive option is the snapshot printer, which offers near-photographic resolution, but snapshot printers are slow and most print only small formats.
Even so, digital cameras are a boon to many people. You can use digital photos in Web pages and documents. Using PhotoCD or a CD-R device, you can store hundreds of photos on a single disk. And, in spite of their limited resolution, home-printed photos are faster and cheaper than professionally printed photos from film.
A medium is a way of communicating information, such as speech or text. Multimedia is the use of more than one unique medium at a time. Multimedia programs are described as interactive if they accept input from the user and enable the user to direct the flow of information or action in the program. The term new media is used to describe the combination of multimedia programming and communications technologies that enable multimedia to be distributed in different ways (such as on disk, via the Internet, or over television).
Effective multimedia programming provides information that is layered and multidimensional. In layered multimedia, multiple types of information may be presented simultaneously. In multidimensional programming, the user can approach information in different ways, such as a text-only description or an animated demonstration.
Navigation is the act of moving through electronic information. Multimedia products typically provide the user with a set of navigation tools.
Hypermedia is commonly used in multimedia products. When the user chooses a hypermedia link, the program moves to a different piece of information, possibly represented by a different type of media.
In creating multimedia products, developers must be aware of the capabilities and features of the user's computer. Hardware and software manufacturers have developed sets of standards for computer systems that will be used with multimedia products.
Multimedia programs are used in a wide variety of ways.
Multimedia is commonly used in schools, where students use CD-ROM-based reference materials and tutorials and use the Internet to collaborate with students in other locations. By using multimedia programs and delivery mechanisms like the Internet and television, schools can support distance learning, which allows students to take classes without actually traveling to school. Online courses are typically called virtual universities. In the workplace, companies commonly use multimedia programs to train employees. These training programs (called computer-based training, or CBT) are sometimes done online but can also be provided on disk. Multimedia is frequently used in the home, whether on a PC, television, or the Internet. Home users consume a wide variety of multimedia products for entertainment and learning.
Creating and Distributing New Media Content
The process of creating a multimedia product usually results from the effort of a group of professionals who follow a multistep process. The development process involves defining the audience, designing the product, choosing development tools, creating content, multimedia authoring, and testing. Multimedia developers must gain a detailed understanding of the audience who will use the final product to make sure it will succeed. Using basic tools such as outlines and storyboards, designers lay out and organize the content and flow of the information for their products. Because a multimedia product can use so many types of media, designers use a wide variety of tools to create individual components, ranging from text editors to video editors. After the individual components of a multimedia product are created, the developer uses sophisticated multimedia authoring tools to assemble them into a single working program.