After you figure out the mechanics of your camera — how to load the batteries, how to turn on the LCD, and so on — taking a picture is a simple process. Just aim the camera and press the shutter button. Taking a good picture, however, isn't so easy. Sure, you can record an okay image of your subject without much effort. But if you want a crisp, clear, dynamic image, you need to consider a few factors before you point and shoot.
Parallax
You compose your photo perfectly. The light is fine, the focus is fine, and all other photographic planets appear to be in alignment. But after you snap your picture and view the image on the camera monitor, you see something different from what you saw through the viewfinder. The framing of the image is off, as though your subject repositioned itself while you weren't looking. You're not the victim of some cruel digital hoax — just a photographic phenomenon known as a parallax error.
On most digital cameras, as on most point-and-shoot film cameras, the viewfinder looks out on the world through a separate window from the camera lens. Because the viewfinder is located an inch or so above or to the side of the lens, it sees your subject from a slightly different angle than the lens. But the image is captured from the point of view of the lens, not the viewfinder.
When you look through your viewfinder, you should see some little black lines near the corners of the frame. These lines indicate the boundaries of the "real" image — the edge of the frame as seen by the camera lens. If you don't pay attention to these framing cues as you shoot, you can wind up with subjects that appear to have been lopped off at the top.
The closer you are to your subject, the bigger the parallax problem becomes, whether you use a zoom lens or simply position the camera lens nearer to your subject. Some cameras provide a second set of framing marks in the viewfinder to indicate the framing boundaries that apply when you're shooting close-up shots.
If your camera has an LCD monitor, you have an additional aid for avoiding parallax problems. Because the monitor reflects the image as seen by the lens, you can simply use the monitor instead of the viewfinder to frame your image. On some cameras, the LCD monitor turns on automatically when you switch to macro mode for close-up shooting.
Light
Digital cameras are extremely demanding when it comes to light. A typical digital camera has a light sensitivity equivalent to that of ISO 100 film. As a result, image detail tends to get lost when objects are in the shadows. Too much light can also create problems. A ray of sunshine bouncing off a highly reflective surface can cause brown highlights— areas where all image detail is lost, resulting in a big white blob in your picture.
When you take digital pictures, capturing just the right amount of light involves not only deciding whether to use a flash or external photographic lights, but also figuring out the right exposure settings to choose.
Keep in mind that you can correct minor lighting and exposure problems in the image-editing stage. Generally speaking, making a too-dark image brighter is easier than correcting an overexposed (too bright) image. So if you can't seem to get the exposure just right, opt for a slightly underexposed image rather than an overexposed one.
Exposure
Exposure refers to the amount of light captured by the camera. Most consumer-level digital cameras feature autoexposure, sometimes known as programmed autoexposure, in which the camera reads the amount of light in the scene and then sets the exposure automatically for you. In order for your camera's autoexposure mechanism to work correctly, you need to take this three-step approach to shooting your pictures:
1. Frame your subject.
2. Press the shutter button halfway down and hold it there.
The camera analyzes the scene and sets the focus and exposure. After the camera makes its decisions, it signals you in some fashion — usually with a blinking light near the viewfinder or with a beeping noise.
If you don't want your subject to appear in the middle of the frame, you can recompose the image after locking in the exposure and focus. Just keep holding the shutter button halfway down as you reframe the image in your viewfinder. Don't move or reposition the subject before you shoot, or the exposure and focus may be out of whack.
3. Press the shutter button the rest of the way down to capture the image.
On lower-end cameras, you typically get a choice of two autoexposure settings — one appropriate for shooting in very bright light and another for average lighting. Many cameras display a warning light or refuse to capture the image if you've chosen an autoexposure setting that will result in a badly overexposed or underexposed picture. Higher-priced cameras give you more control over autoexposure
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