digital slr cameras?
Choosing a Digital SLR Camera
|Digital SLRs offer speed, versatility, and exceptional picture quality. (Sony Alpha SLT-A37 Kit shown)|
Seeing a lot of digital SLRs around these days? No wonder. As digital cameras have gotten more popular and capable, many point-and-shoot users have graduated to the exceptional picture quality and responsiveness of a digital SLR. In this article, we'll give you the details on what makes a camera an SLR, and what differences in performance and features today's digital SLRs deliver.
What exactly is a digital SLR?
An SLR, or single-lens reflex, camera usually consists of a camera body and one or more detachable lenses. It's called "single-lens reflex" because its viewfinder uses the reflection of a 45° angled mirror to let you see your subject through the camera's lens while composing your picture. The mirror lifts out of sight briefly when you press the shutter button, allowing the image sensor to capture the photo.
Why do people use digital SLRs?
The SLR design tends to deliver more precise, dynamic photos, because it usually offers a better lens, larger image sensor size, and more extensive manual controls than typical point-and-shoot cameras. It also provides faster internal processing for greater responsiveness; whereas many point-and-shoot users experience some degree of lag time when they push the button to take a picture, an SLR responds instantaneously to a press of the shutter button. That means you'll capture your subjects at exactly the right moment, resulting in fewer missed shots. Finally, the ability to switch lenses depending on what your subject happens to be gives SLRs a degree of versatility unmatched by smaller pocket cams.
Do I need to be an expert photographer?
Not at all — today's digital SLRs offer easy automatic shooting. In fact, many people who go the SLR route aren't experts; they just want the gorgeous photos that SLRs tend to produce. Of course, if you aspire to more creative shooting, you're all set. SLRs have full manual functionality. And with a digital SLR, learning as you go along is extremely affordable. That's because there's no need to pay to develop unusable photos — you just try out an exposure setting, check the results, delete the shots that didn't work, and try again.
What features should I look for?
You'll want to look for a lot of familiar features common to all digital cameras, such as megapixels , the lens' optical zoom ability, and LCD size (see Digital Cameras: How to Choose). Below, you'll find descriptions of features that can be especially important to choosing and using an SLR:
In general, image sensors that are physically larger can capture tiny highlights or shadow details better than sensors that are smaller sized but have the same megapixel count. Some of the most advanced SLR cameras even offer "full frame" sensors that have the same dimensions as a frame of 35mm film. All that extra surface area offers superior light gathering ability as well as lower noise levels for cleaner looking images. So if you want the most nuance possible, check for sensor size as well as megapixels (see Details for sensor size listed with each SLR camera model).
Finding a digital SLR that will work with lenses you may already own gives you a lot more options (and can potentially save you lots of money). For example, Canon's Digital Rebel T2i works with over 60 current and older Canon EF and EF-S lenses. (Remember: Because imaging sensors are usually smaller than a full frame of film, lenses made for film SLRs may have a different effective focal length when used with a digital SLR.)
|An SLR "kit" includes a lens or two to get you started (top). With a "body only" camera, you'll need to use your own lenses (bottom). (Canon EOS 5D Mark II shown)|
"Kit" versus "body only"
Many digital SLRs are available as kits that include both the camera body and a lens to get you started. The lenses included with most kits make a good basic choice for all-around photography, and can sometimes be a bargain compared to buying a lens and body separately. However, more experienced photographers often buy just the body, then add specialized lenses with long-range telephoto, wide-angle, or close-up capabilities to suit their particular style of shooting. (See Tara's Choosing and Using a Lens for an SLR article for helpful, detailed info.)
Image stabilization (IS)
This highly useful feature (called Vibration Reduction by Nikon and SteadyShot by Sony) comes available to digital SLR users in two different ways:
- As an integral part of an IS lens attached to the camera
- Built into the camera body itself
Either way, image stabilization counteracts the effects of camera shake to let you take sharper pictures in low-light settings and at slower shutter speeds. SLR camera bodies with built-in IS have the added advantage of providing stabilization capability no matter what lens you use with them.
Continuous shooting mode
Continuous or Burst shooting mode allows you to press and hold the camera's shutter button to capture a series of shots in rapid succession. If you're likely to photograph sports or fast-moving subjects like pets and toddlers, you'll want to consider an SLR that offers a higher continuous shooting rate. Most digital SLRs let you take full-resolution photos at a fixed rate of 2.5 frames-per-second (fps) or more. Some even allow you to adjust the frame rate to higher or lower speeds to accommodate the situation.
While you're shooting, the images that you take are temporarily stored in the cam's buffer memory and then written to your memory card. An SLR with a larger buffer lets you shoot more frames at the highest continuous speed before the buffer fills up. When this happens, your frame rate drops to a much lower speed as the camera sends each picture to the memory card before accepting another photo.
HD Movie mode
Until recently, if you wanted to shoot video with a digital camera you needed a point-and-shoot model. But most all digital SLRs are now offering HD video recording capability. The most advanced models give you full manual control of focus and exposure settings, as well as selectable frame rates for more creative control over the look of your movies. Some also provide external microphone inputs for capturing higher-quality sound. Plus, an SLR's ability to swap out lenses can add some new and interesting perspectives to your moving pictures. An SLR might not have form-factor conveniences that some camcorders do, but it's nice to have the option on the camera you have with you, rather than having to carry a second device just for video.
Like most digital cameras, digital SLRs use removable flash memory cards, such as a Memory Stick®, a CompactFlash™ card, or a Secure Digital® card, to store digital photos. If you already own a number of cards of a particular variety, choosing an SLR that uses the same type of memory can make your selection more cost effective. In any case, most digital SLRs don't come with any memory included, so you'll probably want to buy at least a couple of high-capacity cards (8GB or more) — it's amazing how quickly you can fill up a memory card shooting the kind of large, detailed photos that digital SLRs can capture.
Are there alternatives to a digital SLR that offer the same versatility and picture quality?
Over the last couple of years, a number of manufacturers have introduced a new category of camera known as Mirrorless Interchangeable Lens Cameras (we call 'em Hybrids for short). Hybrids share many of the same features and advantages of SLRs, such as their large-sized image sensors for highly detailed photos and low-light shooting prowess, and of course, the ability to swap lenses to match specific shooting conditions.
Unlike SLRs, Hybrids don't use an internal mirror to transmit images of your subject through the lens to an optical viewfinder. In fact, many Hybrids don't have viewfinders at all, and the ones that do use an electronic finder rather than the optical ones found on SLRs. By eliminating the mirror (and the bulky mechanism around it required to make it work) Hybrids have the advantage of reduced size and weight, taking up way less space in a backpack or handbag. And the lenses they use are smaller, too, making an entire Hybrid "system" more compact overall.
But SLRs have been around a long time, and the number of lenses plus other accessories they can use still far outnumber the choices available for Hybrids. If you're looking to put together an extensive photographic system for some serious shooting, an SLR is still be a better bet.
I think I'm ready for an SLR, is there anything more I should know?
We want you to love whatever camera you get. If you're thinking of adding a digital SLR to your photographic arsenal, there are two things we suggest you consider:
|Crutchfield graphic designer, Erica, enjoys the best of both worlds. Her point-and-shoot camera always goes with her on hiking trips, while her digital SLR makes the scene when she shoots weddings.|
Size and weight
If you're used to a pocket-sized camera, make sure you're ready for the larger size and weight of an SLR. Most digital SLR owners feel that the improved response time, versatility, and picture quality are worth toting some extra bulk, but you should decide whether that trade-off is right for you.
With a digital SLR, the viewfinder is traditionally used to frame a shot before snapping the photo. That's still widely recommended for more stable shots and the precise, through-the-lens image provided by the camera's viewfinder. However, folks who have been using point-and-shoot cams are often accustomed to framing their shots with the LCD. That's why many newer SLRs now offer "live view" modes for their LCDs that let you compose your shot on the large screen. Be aware though, using live view mode often means sacrificing the speed and responsiveness SLRs are known for, and introducing the kind of "shutter lag" you find on point-and-shoot models. So we suggest using your viewfinder whenever you can — even if it feels different at first, you'll have a better shot at capturing the picture you want.
If this sounds fine, you're well on your way to digital SLR happiness. If you're still not sure, it may help to spend some time handling one of these cameras. You'll rapidly get a sense for whether SLR shooting makes sense for you.