Digital Cameras and Imaging

One of the main reasons digital cameras are gaining wider acceptance is because of their compatibility with desktop computing and the Web. With relatively little or no technical expertise, a person can take a picture, view it, delete it (if it's unacceptable), and within minutes upload the good images to a computer. Then they can be displayed on the Web or sent via email. The main reason the process is so quick is that instead of taking the photo, having the photo developed, and then having it scanned to create a digital image, the photo is already digitized when the picture is first taken. In this section we will take a look some of the important attributes you may wish to consider before purchasing a digital camera. We will also discuss how to transfer photos from your digital camera to your computer.

Keep in mind these are general guidelines. Digital cameras range dramatically in terms of price and features.

Types of Digital Cameras

Digital photographs are made up of thousands of small dots known as pixels. The more pixels available for defining a picture of a given width and height, the better the quality of the picture. Pixel information is sometimes given in terms of width and height and sometimes in terms of the product of these two numbers; e.g.,1280 x 960 = 1,228,800 pixels or (about) 1.3 megapixels. A camera in the 5 megapixel range (2560 x 1920) is capable of taking high resolution, professional-quality digital photographs. Of course, the higher resolution digital cameras cost more, but the industry trend is toward better resolutions at a more affordable price.

Inexpensive digital cameras (less than $500) are often referred to as "point and shoot" cameras because they are convenient to carry around and usually operate automatically in terms of lighting and focusing. A 1.3 megapixel camera is fine for creating images for use on the Web or to send as email.

Digital images can also be processed into regular prints. There are many sites on the Web where you can upload your camera's images and have them printed and sent to you for a small fee. A 1.3 megapixel camera can produce a good quality 4" by 6" print; a 2.2 megapixel camera can produce a quality 5" by 7" print.

Because computer screens have lower resolutions than print, it doesn't take an expensive camera to capture good looking images for the web.

Say Goodbye to Film

Instead of using film, digital cameras record and store pictures electronically. When the devices on which the images are stored can be physically taken out of the camera, they are known as removable media. There are many types of removable media but four of the more well-known types are: CompactFlash memory cards, CompactFlash II memory cards, SmartMedia memory cards and MemorySticks. CompactFlash and SmartMedia cards are small, square wafers of various thickness that load in the camera. Each digital camera comes with some type of removable storage, and additional storage is available. However, the different formats are not interchangeable.

Some digital cameras use magnetic disk technology because they can hold more data. This technology includes floppy disks (like the ones you can use in your computer), small microdrive hard drives, and Iomega Clik! drives. When you consider purchasing a digital camera, you should be aware of which technology storage format the camera manufacturer has embraced.

Batteries Are Important

No matter which digital camera you choose, rechargeable batteries are a necessity. Most point and shoot cameras will run on AA alkaline batteries. But since a digital camera requires power to save an image, focus, and zoom, it can drain a set of alkaline batteries very quickly.

One alternative is the rechargeable Nickel Metal Hydride battery (NIMH), which come in the AA size. They are environmentally safe to dispose (unlike the Nickel Cadium NiCad batteries which contain toxic materials), and they power a digital camera significantly longer than alkaline. Some digital cameras also take lithium and lithium ion batteries. Lithium batteries have two or three times the capacity of alkaline batteries and they hold their charge well when in storage. Lithium ion batteries are rechargeable. On the downside, both lithium and lithium ion batteries are more expensive than alkaline and NiMH batteries.

Loading Images: From Camera to Computer

When you purchase a new camera it usually comes with software and cabling that allows you to connect your camera to the computer. The camera can be connected to your computer with a serial or USB (Universal Serial Bus) cable. Serial connections make for very slow downloading. More and more cameras now come equipped with a USB connector cable, which can make file transfer to the computer much faster.

Another approach to file transfer from camera to computer is provided by a card reader; this is a small, mouse-sized device that connects to the computer through a USB port. Some card readers can read only one type of storage media (e.g., SmartMedia or CompactFlash), but there are readers that will read multiple types of media. It's critical that you match the loading device with the removable storage media you are using.

Yet another way to load images is to place the memory card inside a floppy disk adapter (a device that looks like a floppy disk) and then insert it into the 3 1/2" disk drive of your computer. For notebook computers, there are card adapters (these look like credit cards) that allow the memory card to be inserted into the PC card slot of the notebook computer.

Final Note

There are many good web sites that cover digital cameras and digital photography more thoroughly. If you visit Steve's Digicams or A Short Course in Choosing a Digital Camera, you'll get more depth and detail on the topics we've mentioned. We've only scratched the surface of this rapidly changing technology so you can get started taking and loading pictures into your computer. From there you can post them to the web, send them in email, or add images to your own documents and presentations.