Digital SLR Photography All-in-One For Dummies. Robert Correll
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Image stabilization
Image stabilization is important when shutter speeds are slow and you are supporting the camera by hand. Camera movement robs you of a sharp photo. All new digital SLRs from the major manufacturers steady the image using one of two different approaches:
❯❯ Lens: The image is stabilized in the lens, not in the camera body. Current lens-based stabilization systems are named differently, depending on the brand of camera. Canon calls its approach Image Stabilization (IS). Nikon uses the term Vibration Reduction (VR; see Figure 1-18). In both cases, the lens has a floating optical element that, when turned on, is gyroscopically stabilized. Subject to some limits, the IS/VR unit in the lens moves in opposition to camera movement. This keeps the image focused on the image sensor rather than jumping around.
Th advantage to lens-based stability systems is that everything benefits from stabilization: the autofocus system, the image sensor, the metering sensor, and what you see through the viewfinder or on the back monitor.
The main downside to lens-based image stabilization is that not all lenses have the feature. In addition, you have to keep buying new lenses to benefit from improvements and updates to the technoleogy.
❯❯ Sensor: This type of image stabilization occurs in the camera body. The camera adjusts the position of the image sensor in opposition to camera movement, thereby enabling you to capture a clear photo. Sony calls its technology SteadyShot (see Figure 1-19) while Pentax refers to its system as Sensor-shift Shake Reduction. Olympus features 3- or 5-Axis In-Body Image Stabilization; newer Sony’s a7-series full-frame mirrorless models are equipped with 5-axis image stabilization as well.
The main advantage to body-based stability systems is that the sensor, and therefore the image, is stabilized no matter what lens is attached to the camera. The most expensive long-range super-telephoto lens in the world and the cheapest plastic lens will both benefit from in-camera stabilization. As you upgrade camera bodies, you get the latest and greatest implementation of image stabilization for all your older lenses.
FIGURE 1-18: Nikon’s lens-based image stabilization technology is called VR.
FIGURE 1-19: This camera features in-body image stabilization, complete with an on/off switch.
Following Recent dSLR Developments
Digital SLRs continue to evolve. That is truly fantastic news, because photographers benefit from new capabilities and technology. Here are some recent dSLR developments and trends:
❯❯ Wi-Fi/NFC: After lagging behind for many years, built-in Wi-Fi/NFC (near-field communication) features are becoming more prevalent in new dSLRs. You can connect your camera to a smartphone (see Figure 1-20), tablet, computer, printer, network computer, or the Internet to view, print, or transfer photos. You can often control the camera remotely using the same connection and the proper app.
❯❯ Touchscreens: Taking a cue from the popularity of smartphones and tablets, some new digital SLRs feature touchscreen monitors. You can drag, swipe, and tap through menus, photos (see Figure 1-21), and even use the touchscreen to focus and snap the shutter.
❯❯ In-camera processing: Look for cameras to have even more processing options and filters.
❯❯ Higher ISO speeds: Maximum ISO speeds continue to rise. Entry-level consumer cameras now have maximum ISOs in the range of 12800, while more advanced dSLRs can have astronomically high ISOs. Higher ISO speeds make shooting inside and in other low-light conditions easier. They also enable you to use less-capable lenses with smaller maximum apertures in a wider variety of conditions.
❯❯ Higher pixel counts: Pixel counts also continue to rise. New consumer-level dSLRs have more pixels than professional models from years past. This means that you can take photos and make poster-sized prints without losing quality. You can also crop photos more without losing too much resolution.
❯❯ Expanded shooting modes: Today’s dSLRs offer more creative shooting modes and scenes than ever before.
❯❯ 4K Video: Today, all new dSLRs shoot Full HD movies, and the new trend is 4K video, which quadruples the resolution of Full HD (or 2K video, depending on the camera you’re using).
❯❯ Articulated monitors: More cameras feature articulated monitors that swing out from the back of the camera. This feature gives you greater flexibility in how you hold and position the camera. See Figure 1-22.
FIGURE 1-20: Increased Wi-Fi support is a positive dSLR development.
FIGURE 1-21: Selecting a photo to view from the index view.
FIGURE 1-22: Pull the monitor out from the back of the camera and position it.
Shopping for a dSLR
Shopping for a dSLR doesn't have to be stressful. In fact, it can be downright fun. I offer you this general guide as someone who has “been there and done that” many times over the last several years. Be honest with yourself about your budget, what you want out of a camera, and the type of photos you want to take. Brush up on the dSLR categories and general specifications so that information about different features and capabilities is fresh in your mind before shopping.
Understanding the system
When you buy a digital SLR, you’re buying into a system from a specific manufacturer, such as Canon, Nikon, Pentax, or Sony. You can't mix and match lenses (other than third-party lenses that are compatible with your system), camera bodies, flash units, or other accessories produced by different camera manufacturers. If you have already heavily invested in a specific brand, you’ll have a harder time switching and gearing up with your new camera.
Going shopping
To shop for a digital SLR, follow these simple steps:
1. Set a budget.
There’s no sense in looking at a $3,400 camera if you can’t afford it. Seriously, you will read accounts and people will tell you how much better that $3,400 camera is than the $800 model you’re looking at until you’re sick of it. Though they may be right in terms of some capabilities and technical details, their advice is entirely irrelevant to you and your decision. Your budget depends on you and is probably based largely on factors unrelated to photography.
Therefore, set an initial budget. It will save you time and frustration. Your budget will help you identify the cameras you should look at in the next step. Look for a sweet spot where your needs meet the price you can afford and the performance you want. Don’t forget to factor in lenses, bags, tripods, filters, flashes, extra batteries, and remote shutter releases. Those things all add up. If money is no object, look instead at the dSLR categories I listed earlier and decide what level of camera you want to buy. This will narrow your search to more manageable proportions.