photos, whereas another is adept at hurrying photos along to the storage space on memory chips.
The other type of chip is less of a brain. It’s more like an idiot savant that mindlessly performs a job
other microchips would be hopeless at. This chip, called an image processor, is covered with a spe-
cial type of transistor—millions of them—that is sensitive to light and converts that light into electricity.
It takes the place of film.
The image sensor’s capability to translate different colors and intensities of light into constantly chang-
ing electrical currents is what accounts for the other important differences between digital and film
cameras. The most obvious can be seen on digital cameras in the form of the LCD screen on the back
of them, like a tiny TV set, where the camera displays the scene to be shot or the photographs
already stored in the camera. The LCD has its own array of transistors that do just the opposite of the
image sensor’s transistors: They convert electricity into light.
If you inspect the two cameras closely enough, you may find some other differences. The digital cam-
era may have, for example, a button or switch for something called white balance. Or have controls
for on-screen menus, or for displaying information about a shot you’ve snapped. It may have a dial
with icons on it for shooting sunsets, close-ups, or fast-moving sports, or a button with a trash can on
it like the one used for deleting files on a PC. The differences in digital cameras lead to differences in
how you shoot pictures, how you use software to process them—the digital equivalent of developing
film—and how you print them. But much of what you’re used to with film cameras works the same
with digital equipment. You still need to put some thought into how you frame your picture. You still
must expose the photo correctly. You need to focus the lens on what’s important. Digital cameras help
you do all of that. But you’re on your own when it comes to developing the skill to push the shutter
button at the moment of visual truth.
Once you click the shutter, letting light fleetingly strike the image sensor, you’ve created not just one
picture, but the possibility for scores of pictures. And as you’ll see later, the future of that picture is
limited only by your imagination, and even that is likely to grow as you become more familiar with
the possibilities of digital photography.
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