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A digicam with a built-in lens can be convenient, but many photographers prefer an SLR that accepts a full series of lenses (see Figure 1.9). The term Single Lens Reflex refers to the fact that you view the scene through the same lens that takes the picture. A system of mirrors in a prism reflects the image to the camera’s viewfinder so there is no need for a secondary viewing lens above the “taking” lens. Because you view the subject through the “taking” lens, framing is more accurate in close-focusing without the parallax error that occurs with a separate viewfinder. The view is also bright and crisp because the viewfinder is optical and not electronic.
Figure 1.8: A digital SLR system includes cameras and a variety of lens types and accessories such as flash units. [F0110.tif]
Courtesy Olympus America
A Note on TerminologyAs mentioned earlier, compact digicams—with built-in long telephoto zoom lenses—also offer through-the-lens viewing, but these employ a small LCD screen (EVF) in the viewfinder. Such cameras are also SLR models, but in practice, the term SLR is generally used only when discussing the cameras that accept interchangeable lenses and employ a prism for through-the-lens viewing. Consequently, I’ll use the term SLR only when discussing cameras that accept interchangeable lenses. An SLR camera system includes lenses from ultrawide-angle to super telephoto, allowing you to achieve any desired effect. They have other advantages over the compact cameras. Typically, SLRs offer more advanced digital and conventional capabilities and more options to image capture format. Although an SLR camera can be complicated, it can also be as simple as you want, in its fully automatic program mode with image adjustment controls at the default settings. |
Most digital SLR cameras include the capabilities that serious photographers expect: high-speed continuous focus for tracking action subjects (see Figure 1.9); built-in flash plus compatibility with accessory flash units; automatic, semiautomatic, and manual modes; numerous overrides for controlling every aspect of an image; depth-of-field preview for assessing the range of sharp focus; and a great deal more. They offer at least two recording formats: JPEG for small image files even in high=resolution imaging and a proprietary RAW mode for very high picture quality without excessively large image files. Many even include a third option: TIFF image capture for the finest image quality, though as discussed previously, this can result in slow recording times and huge files that quickly fill up a memory card.
Figure 1.9: One of the primary advantages of a digital SLR camera over a compact digicam is faster speed in framing and in autofocus. This benefit is particularly important in action and wildlife photography.
Most digital SLR camera kits include the camera body, a cable for connecting the camera to your computer, a CD with software, rechargeable battery and charger, and possibly a low-capacity memory card. A lens is not included, although some retailers sell kits, at a higher price, that include an affordable zoom lens that will get you started if you do not already own suitable lenses.
Four years ago, the most affordable digital SLR camera cost as much as a good used automobile and boasted an image sensor with only 2 million pixels. Today, you can buy a 6-megapixel digital SLR for $1000, and it will generate much larger image files than its precursor, with substantially higher resolution.
As the “cons” in the compact camera section imply, a digital SLR camera offers benefits, particularly in terms of superior image quality and versatility. Although lens adapters—used with a prosumer digicam—can be useful, SLR cameras accept a far more comprehensive range of lenses; these also produce higher image quality than lens adapters.
A digital SLR camera body is certainly more expensive than a compact camera, and it does not come with a lens. If you already own a Canon, Sigma, Pentax, or Nikon autofocus SLR camera, with suitable autofocus lenses, your lenses will be compatible with a digital SLR camera of the same brand. In that case, your investment need not be excessive. And the investment will pay off in the long run, because you’ll save money on film and processing.
Finally, you’ll find that most of the SLR models are loaded with all the capabilities and overrides that will satisfy advanced photographers. The best cameras produce images with ultra high resolution, suitable for beautiful prints as large as 13 ? 19~IN, and even larger if the images are enhanced and printed with some expertise.
Recommendation: Compact Digicam or Digital SLR Camera?An SLR camera, plus lenses, costs far more than a compact digicam with a built-in lens, and an SLR is larger, heavier, and substantially more complex. Hence, this is not the right choice for everyone. But if you’re a photo enthusiast who uses a 35mm SLR camera when shooting film, you’ll certainly want to consider a digital SLR camera. ($899 and up, plus lenses.) In addition to the creative and problem-solving abilities available with a variety of lenses and extra features, an SLR camera offers another significant benefit over a compact model: superior image quality because it employs a larger image sensor—with larger recording pixels—than a compact digicam. If you will not need the additional versatility available with a wide range of (expensive) lenses and the extra capabilities available with an SLR camera, or if you do not plan to make very large prints, a highly rated compact digicam should meet your needs. Look for test reports on the Internet to determine which specific models are “best.” For the maximum versatility with a compact digicam, consider one of the 4+ megapixel prosumer models that boasts many of the same capabilities as SLR models and also accepts wide-angle and telephoto lens adapters as well as accessory flash units. Although the accessories are not inexpensive, they do increase a camera’s versatility. Some digicams include a wide range (6x to 10x) optical zoom lens, and one of these cameras may provide all the focal lengths that you will want. The only drawback is that such cameras use an electronic (instead of optical) viewfinder, and not everyone finds an EVF convenient to use. |
Next week, we continue with Part 2 of Chapter 1: Essential Digital Imaging Equipment, from Mastering Digital Photography and Imaging, by Sybex. Next week, we open with a discussion about Professional Studio Cameras.
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