January 2008 • Vol.19 Issue 1 Page(s) 44-45 in print issue | |
D-SLRs (digital single-lens reflexes) differ from point-and-shoot cameras because they allow photographers to have better control over the image they want to achieve. With that said, you don’t need to be a professional photographer to own and operate a D-SLR—you only need the desire to take high-quality photos. Here, we explain the most important things to know as you shop for your first D-SLR.
Exposure Controls Exposure controls allow you to manually control the camera’s aperture and shutter speed, which work in tandem to control your depth of field (the parts of a scene that stay in focus) and exposure (the amount of light that falls on a camera’s image sensor). Aperture controls the camera’s lens diameter and how much light will hit the image sensor (a chip inside your camera that captures images just like film). When your lens has a large opening, more light hits the image sensor, making your image sharper. You’ll find that a camera’s aperture is measured in f-stops, and the smaller the f-stop number (or f/value), the larger the lens opening will be. Shutter speed dictates the amount of time light is exposed to the image sensor. A quick shutter speed is important when you’re photographing at athletic events; it will ensure you don’t miss a shot or have blurry images.
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ISO speed ratings determine how sensitive your camera is to light. For low-light situations, you will need a higher ISO rating, which makes your camera more sensitive to light. A word of caution: High ISO settings can make your photos look grainy (also called noise); however, you can avoid noise by purchasing a professional-grade D-SLR with a large image sensor. ISO speeds are generally around 100, 200, or 400, but more expensive models can get as high as 6400. To give you a better idea, ISO 100 is considered the “normal” setting and will work best in bright or well-lit environments. An ISO of 400 or more is used to take a photograph in low-light settings without a flash. Speeds of 1600 and more are used by professionals for artistic purposes.
The difference between optical zoom and digital zoom on D-SLRs can be confusing to consumers. Optical zoom changes the focal lengths of the camera lens. With digital zoom, the camera uses software to crop out a portion of an image, enlarges it, and fills in missing pixels, which can sacrifice your image quality. Unlike D-SLRs, point-and-shoot cameras offer mostly digital zoom capabilities with limited optical zoom. If you purchase your D-SLR as a kit (a D-SLR body and lens packaged together), your kit lens will likely have a limited optical zoom lens. But if you’re interested in telephotography (taking pictures of faraway objects, such as wild-life in a distant setting), you may want to purchase a telephoto lens, which will be sold separately.
What sets digital SLR cameras apart from traditional film SLR (single-lens reflex) cameras are image sensors. Image sensors consist of pixels that interact with light to create your image. The two common types of image sensors are CCD (charge-coupled device) and CMOS (complementary metal-oxide semiconductor).
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Many first-time D-SLR buyers make the mistake of looking for a camera with the highest megapixel count, because they assume that more pixels means better image quality. While the number of megapixels is important, you probably won’t need a D-SLR with anything more than 7 or 8MP (megapixels). Megapixels don’t increase the quality of the image, but rather they make the image bigger in size for printing purposes. For example, if you want to create crisp, clear 8- x 10-inch prints, a camera with 7 or 8MP will suffice. If you wish to create poster-sized prints for artistic or professional use, consider finding a D-SLR with 10MP or more. Optics and exposure settings—aperture, shutter speed, ISO speed, etc.—often outweigh a D-SLR’s megapixel count by more serious photographers
The LCD is where you’ll view your D-SLR’s menu and photos, so be sure the menu is easy to access, understand, and read. LCDs will vary in size, and they can be anywhere from 1.8 to 3.5 inches. Your screen should be big enough for you to view your photos clearly because you will be using it to play back your images. Traditionally, D-SLR models require you to look through the optical viewfinder, but some newer models let you use the LCD as a viewfinder to frame your pictures like you would with a point and shoot. Another factor to consider is LCD washout, which can happen when sunlight hits your screen. Some models have special LCDs made to avoid washout.
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When you are first learning how to use a D-SLR, it can be difficult to know how to adjust the camera correctly in manual modes. Most models have preset modes that automatically adjust your camera in different conditions. Modes can include landscape, portrait, action, night, and macro.
When budgeting, don’t forget to purchase external memory cards; usually the D-SLR’s internal memory isn’t sufficient enough to use. The two most common types of memory cards are CF (CompactFlash) and SD (Secure Digital), but there are plenty of others available on the market. Your camera’s users manual will tell you what kind of memory card you need to buy.
D-SLR cameras are a big investment, so be sure you get the right accessories. Purchase a bag that has plenty of compartments, because when you travel with your D-SLR, you will want to carry extra lenses, batteries, and a soft cleaning cloth. Also, consider where you’ll be going with your camera. If you plan on taking it with you on your annual biking trip, you may want to find a bag that functions like a backpack.
Most cameras will come with a proprietary battery, but you may want to purchase a second for backup. Battery life is affected by features such as the LCD and flash, so it’s hard to tell exactly when your battery will give out on you. You don’t want to realize your battery has just died the next time you want to snap a beautiful shot.
by Tessa Warner Breneman
| Camera Box Acronyms As you research D-SLR (digital single-lens reflex) cameras, you might run into a few acronyms you are unfamiliar with. Here are some definitions that will help you as your shop for a D-SLR.
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