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Digital Single-Lens Reflex cameras at a glance
Best suited for:
- Access to wide range of interchangeable lenses
- Prism viewfinder means you see directly through the lens
- Ultimate control: full manual exposure, full auto, or anywhere in between
- Very customizable
- Fast autofocus; can switch to manual focus
- Add-on flash is stronger than built-in camera flashes
- Can be used with multiple flashes or studio lights
10 things you can shoot much more easily with a DSLR:
- Sports
- Nature
- Wildlife
- Photojournalism/Candids
- Portraits/Weddings
- Studio photography
- Low-light photos
- Travel
- Astrophotography
- Macro photography
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If photography is your passion, there is no doubt: you should own a single-lens reflex (SLR) camera. Digital SLRs allow you to experience photography at its best. They are the tool of choice for professional photographers around the world; remember, pros will never settle for second-best. And now, thanks in part to their growing popularity, Digital SLRs are more affordable than ever.
WHAT IS A DIGITAL SLR?
The abbreviation "DSLR" stands for Digital Single Lens Reflex. That means you are looking at the subject directly through the lens, and seeing exactly what the camera's imaging sensor sees. (In truth, "exactly" isn't exactly correct--you see between 95 and 99 percent of what the camera sees.) It may seem that we could say the same thing about any digital camera because you can see a "live" image of the subject on the LCD monitor. However, non-SLR cameras work quite differently--they show you a video version of the scene.
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Stop action: Sports and action photography is one of many things digital SLRs do better than any other kind of camera.
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DSLR ADVANTAGES
The first and most significant advantage of a digital SLR is the fact that you can remove the lens and attach a different one in its place. That means you can use long, long telephoto lenses for sports or wildlife photography, macro lenses for dramatic close-ups, fisheye lenses, and so forth. Most people purchase a DSLR with a zoom lens that covers semi-wide angle through moderate telephoto, often something in the 18-50mm or 18-70mm range. Since nearly all DSLRs borrow much of their design from film-camera SLRs, you can use many of the same lenses that were created in the analogue era. This explains the wide variety of lenses that are available.
SENSOR
The image sensor, either CMOS or CCD type, ranges between 6 and 8-megapixels for consumer DSLRs and 8-megapixels or higher for professional level cameras. For many photographers, low image noise is more important than more megapixels. Image noise is a random pattern of discolored pixels that looks like specks of colorful dust. It usually appears when the ISO, or sensor sensitivity, is set at one of the higher levels.
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David or Goliath? You can see the difference in these cameras' sensor sizes by looking at the mirrors, inside the circular lensmount. The big, 16MP, Pro-oriented Canon EOS 1 Ds Mark II (left) has a 35mm-sized sensor, while the amateur-level Nikon D50 has a smaller APS-sized sensor. The two cameras also give you an idea of the range of sizes of digital SLRs. The price spread? The Canon costs around $6,000, while the Nikon costs less than $600!
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SENSOR SIZE AND NOISE
The good news, when it comes to noise, is that all DSLRs will outperform compacts and most EVF cameras. That's because DSLRs have larger sensors. So, if you compare an 8-megapixel DSLR sensor to a compact camera's 8-megapixel sensor, the pixels on the DSLR sensor can be made larger. The larger the pixels, the less chance there is for there to be signal distortion, which causes noise.
SENSOR SIZE AND LENS COVERAGE
The size of the imaging sensor in most DSLRs--especially in lower-priced models--is much smaller than one frame of 35mm film, and that causes the lens to magnify at a different ratio. (Note that there are DSLRs that use a full-sized sensor; the majority, however, do not.) The effect is a factor about 1.5X (1.6X in the case of some brands, including Canon). If you shoot with a 200mm lens on a DSLR it will behave like a 300mm, and make objects appear closer. That's a big plus if you want to use a telephoto. But it's an even bigger minus if you are shooting wideangle. A 24mm lens (which is a very wide angle on a standard film camera) becomes a 36mm. To regain the wide angle advantage, you would need to purchase a new, wider-angle lens. A new generation of superwide zooms, built specifically for use with DSLRs, are now available for all models.
If compact, fit-in-your-pocket form factor is an absolute must, then a DSLR is probably not for you. A typical DSLR is larger than a point-and-shoot digital camera, and you're not going to be able to stuff one in your pocket. The good news? Some lower-priced DSLR models are quite compact and very light weight, even if they're not going to fit in your pocket.
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Just right: Digital SLRs offer the kind of fine exposure control pros demand. Experienced users can control a group of flashes from some DSLR to create perfect in-studio exposures, and the higher-megapixel models will give magazine- and even poster-quality resolution.
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EXPOSURE CONTROL
Digital SLR cameras offer various exposure modes that differ slightly from brand to brand:
- Fully automatic Programmed exposure mode choses the right settings for you.
- Shutter Priority--you choose the shutter speed (useful when trying to freeze moving subjects)
- Aperture Priority--you select the aperture (f/stop) to control the depth of field while the camera sets everything else
- Full manual operation (make all of the settings on your own).
DSLRs offer the greatest growth potential--you can grow into the camera's features even if you're just a casual snapshooter.
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Freeze far-away action: A long, fast, close-focusing zoom lens, high ISO setting, and a DSLR with a shutter release that doesn't hesitate when you press it--and, of course, the hummingbird, are all the ingredients necessary to capture a great stop-action shot like this.
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ZERO SHUTTER LAG
Another advantage of a DSLR is that they have nearly zero "shutter lag." Shutter lag is aggravating--you press the release button but there is an annoying delay before the camera fires. Many perfect shots are missed because some cameras do not respond fast enough. This does not occur with a DSLR.
The main reason the shutter release may be delayed is that the camera will wait until the camera has finished focusing on a subject. The good news is that most interchangeable lenses focus really fast, so lag time is still minimal. Want to eliminate lag time altogether? If your subject isn't moving from shot to shot, focus once, then switch to manual focus. That eliminates the wait for focusing.
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A word about filters: All of the interchangeable lenses available for DSLRs have filter rings, which give you the ability to better control the image at the time of exposure. This shot was made with a neutral-density filter, which darkened the sky so it wasn't too light.
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IMAGE QUALITY
Digital SLR cameras create very large image files. Because of that they also produce tremendous, high quality images. All DSLRs offer the ability to shoot in RAW format, the ultimate format for image tweaking. In order to get the most out of a DSLR image, most people use professional-grade editing software like Adobe Photoshop or Photoshop Elements. Using Photoshop is like having a photographic darkroom right inside your computer. You'll also want to invest in a photo-quality printer. Images captured with any DSLR can easily be printed 16x20 inches or larger with excellent results.
Again, sensor size has a direct effect on image quality, and this is a place where DSLRs have a distinct advantages over compacts and most EVFs. Even the smallest sensor on a DSLR will be larger than the sensors used in compacts and EVFs, and that means bigger pixels (even if the megapixel count is identical), and since pixels are bigger, that reduces the chance of distortion, also known as digital noise. When you're shooting at high ISO settings, you'll notice the difference.
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Something fisheye: Only DSLRs accept true fish-eye lenses, which can capture 180 degrees in a distinctive circular image.
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DISADVANTAGES
There's one drawback--and this is something that many new owners discover AFTER they have purchased their digital SLR--the LCD monitor is for playback only. You cannot compose images on it. All framing and composition must be done with your eye at the viewfinder. But even if it's become a habit for you to take digital shots with the camera held at arm's length and your eye looking the LCD, you'll be able to learn the SLR technique in no time.
The only exception at the moment is the Olympus Evolt 330, which offers a live preview feature. We expect to see the same technology appear on other DSLRs, but not right away.
Digital SLRs do cost more than other kinds of digital cameras, but the prices are dropping. What would've cost $1,500 a year ago can now be bought for under $1,000. The least expensive DSLRs are just a bit above $500.
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