I took most of the photos in this book using the Kodak DC-240 digital camera, shown in Figure 13.1, and used the gPhoto software (described later in this chapter) to transfer the images to disk. Of course, black-and-white printed reproduction doesn't do this camera's images justice.
Cameras that don't store their images, but rather transfer them directly to the computer, are frequently used for displaying real-time images on Web pages. For this reason, such cameras are often referred to as WebCams. Figure 13.3 shows a typical example, positioned next to a roll of 35mm film for scale. These devices are usually quite small and are designed to rest atop your computer or monitor, where they can capture your visage head-on as you use your computer. They vary substantially in shape and size, but they usually include some way to pivot their lenses up and down. They seldom incorporate much in the way of controls; usually just a status LED, one or two buttons, and a focus control.
A WebCam is small and simple, and produces poor images compared to portable digital cameras.
WebCams can be evaluated by most of the same criteria I laid out for portable digital cameras; however, these devices are usually quite inexpensive and limited compared to their portable camera counterparts. For instance, most WebCams produce only 640x480 images, and they generally use crude manual focus mechanisms, such as a rotating ring around the lens. Because you probably intend to use a WebCam for rather limited purposes, these devices' limitations with respect to image quality are not extraordinarily important.
If you intend to use a WebCam for composing video email, creating audio/visual presentations, or similar functions, you must also have a sound card and microphone. I discuss these components in Chapters 10, "Sound Cards," and 11, "Audio Input/Output."
The software used to interface with a WebCam is different from that used to extract pictures from a portable digital camera. Under Linux, you use software developed for the Video for Linux interfaces (http://roadrunner.swansea.linux.org.uk/v4l.shtml) to access a WebCam. The Video for Linux interfaces are included in the Linux kernel. Software ranges from programs to grab individual "snapshots" to TV viewers (which can be used for live video image viewing and extraction from WebCams) to security camera applications.
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To begin with your career in photography at the right path, you need to gather more information about it first. Gathering information would provide you guidance on the right steps that you need to take. Researching can be done through the internet, talking to professional photographers, as well as reading some books about the subject. Get all the tips from the pros within this photography ebook.