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In addition to a basic Program (fully automatic) mode, many digicams include several other options. Extra Program modes, designed for good results with a suitable aperture/shutter speed combination for specific types of subjects, are great for aim-and-shoot simplicity. In my experience, the following Program modes are most often useful: Landscape, Portrait, and Sports.
If you’re an experienced photographer, you’ll also want a semiautomatic Aperture Priority mode that allows you to select a specific f/stop with the camera setting the correct shutter speed to maintain a good exposure. Set a wide aperture (such as f/2.8 or f/4) to blur away a busy background, using the longest zoom setting. Or select a small aperture (such as f/8 or f/11) and a wide-angle zoom setting to maintain sharpness from the foreground to the background in a city scene or a landscape. Some Program modes can achieve a similar effect but Aperture Priority mode gives you greater control.
A Shutter Priority mode is also common, and this feature allows you to set a fast or slow shutter speed, while the camera sets a correct aperture. Some cameras also include a fully manual mode that requires you to set both the aperture and shutter speed, guided by some indicator provided by the light meter. This feature is slow to use and is intended only for the most-experienced photographers.
All digicams include an Auto White Balance feature that automatically adjusts for the type of ambient light: sunny, cloudy, household lamps, and so on. The automatic systems do not always provide ideal results, and some images will have an undesirable color cast. Consequently, most cameras include specific settings to match common lighting conditions. The more options, the better. Simply select the one that best matches the lighting, and you should get excellent images without a color cast. A few prosumer cameras also offer a Custom or Manual Preset White Balance option that allows you to “teach” the camera to render whites as white in a difficult lighting condition—under the sodium-vapor lamps found in some sports arenas, for instance. This feature is most useful if you often photograph under uncommon lighting conditions.
To calculate a correct exposure—good brightness level—digital cameras generally employ a sophisticated “evaluative” or “multi zone” metering system. These evaluate the lighting pattern, ignore ultrabright or extremely dark areas, and set a good to excellent exposure in most situations. The most successful of these systems are highly reliable and may be all that most digicam owners require.
Experienced photographers who are familiar with the use of the less automated Center-Weighted metering system will want a camera that also includes this feature. Some exposure compensation will usually be required for good exposures with light- or dark-toned subjects. Spot Metering is also common in advanced and prosumer cameras and is intended for metering a small subject area such as a spot-lit performer against a dark stage. This feature requires some expertise in selecting an area to meter and in knowing when to increase or decrease exposure; hence, it’s intended only for use by experienced photographers.
Regardless of the type of metering system, in some situations a camera will not provide the ideal exposure; some pictures may be excessively dark or bright. That’s why an exposure compensation dial is standard equipment for controlling image brightness.
This feature allows you to take a picture, check the image in the LCD monitor, and make adjustments for reshooting. If the image is too dark, set a +0.5 exposure compensation level and shoot again. If the image was too bright, set a -0.5 exposure compensation level before reshooting. Sometimes, you may need to use a higher level of compensation for optimal exposures; most cameras offer a range from -2 to + 2 , for a significantly darker or brighter image. Some allow you to select from an even wider range, such as -4 to +4, but you will rarely (if ever) need that capability.
| It’s not always possible to accurately determine whether the exposure was correct by checking the image on the LCD monitor. Image brightness can vary depending on the lighting conditions when viewing the monitor. Ideally, you should view the image in shade and not in direct sunlight. Some prosumer digicams include a “histogram” display, a feature that allows you to more accurately evaluate exposure, particularly loss of detail in shadow and highlight areas. The histogram is discussed in the “SLR Camera Capabilities” section. |
Autoexposure bracketing (AEB) is another common advanced feature; when it’s selected, the camera takes three images in a sequence, varying the amount of exposure by a preselected amount: for metered exposure, overexposure, and underexposure. This can be useful if you want to shoot quickly and are not sure if you need to set exposure compensation.
| If shooting in a camera’s RAW capture mode, you will not often need to use exposure compensation or bracketing. Using the RAW converter software in a computer, you can increase or decrease exposure by up to -2 or +1. That is adequate for most images, in my experience. |
Cameras with built-in flash include common settings such as Auto mode for flash when needed, Off mode for use when flash is not appropriate, and Red-Eye Reduction mode that can help reduce red-eye. Other useful modes worth looking for include Daylight or Forced flash, which triggers flash in bright conditions and is useful for brightening shadow areas, such as those cast over a person’s face by the bill of a hat. Slow Sync flash is intended for long exposures with flash, perhaps to photograph a person in front of a city skyline at night. (Use a tripod to prevent blurry pictures caused by the long exposure.) Finally, a few cameras offer Flash Exposure Compensation or Flash Intensity Adjustment; this feature is most valuable for decreasing flash output outdoors, for a subtle flash effect that yields a more professional look.
If you often photograph distant subjects, you will want to use a high-powered flash unit with greater effective “reach” than the tiny, built-in flash. In that case, look for a camera that’s designed to accept an accessory flash, generally only one that’s made by the camera manufacturer.
Although this is a standard feature—for composing images and for viewing images that you have previously taken—some monitors are better than others. The best monitors are large (at least 1.8~IN diagonal), with high-image resolution (at least 100,000 pixels) and have an antireflection coating for greater ease of viewing in bright light. Some cameras offer Playback Zoom for enlarging portions of the monitor image to check sharpness; this can be a valuable feature.
Digital cameras devour batteries, especially when the LCD monitor is used often, making the familiar alkalines virtually useless because of their low power output. You’ll want a camera that accepts high-capacity batteries either in the AA size or some unusual size/shape in a proprietary battery pack. Rechargeable Lithium Ion or Ni-MH (Nickel Metal Hydride, see Figure 1.12) batteries are the most practical since they offer high-power capacity, last a long time, and can be reused. Avoid cameras that accept only nonrechargeable lithium batteries because those are expensive to replace.
Figure 1.12: Many digital cameras accept the rechargeable Ni-MH batteries in AA size. This type is inexpensive, offers high-power capacity, and can be recharged at least 500 times.
Courtesy of Maha Energy Corporation
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Created: March 27, 2003
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