The heart of any photographic system is its lenses. Over the course of our photographic lives, we can spend a lot of money and time purchasing and using lenses to create our images. Yet whether you're spending hundreds or thousands of dollars on your glass, it can be quite frustrating to find that these lenses, some of which are used by the pros, aren’t delivering the quality you expected. You could have the sharpest lenses ever created, but poor techniques result in a soft image that lacks punch. So, although cold, hard cash buys you a great piece of glass, it's practice and technique that produce an outstanding image. The following tips will help you make the most out of your camera and its lenses.
The way you hold a camera has a huge impact on the sharpness of your images. If you hold a camera incorrectly, unintended camera movement leads not only to blurred images, but also to a reduction of contrast and image brilliance. While the results may not be immediately evident when viewing your photographs on a camera's LCD or casually glancing at a transparency, enlargements quickly reveal the failings of mishandling a camera.
To create a stable platform with your own body, hold the camera with both hands. Support the camera body (not the lens) by cradling it in your left hand and grasp the camera and shutter release button with your right hand. Press your elbows firmly against your body and raise the camera close to your eye. If you're using a digital camera with an LCD, avoid holding the camera away from your body with your arms extended.
Gently depress the shutter release button halfway and maintain pressure to achieve and lock focus. When you're ready to take the image, fully depress the shutter release button.
A tripod provides a stable platform for your camera and is a key means for ensuring sharp photographs. Whether a small tabletop unit or a large carbon-fiber model, a tripod delivers the ability to create sharp images if you're shooting under low light before dawn or in bright sunlight.
The advantage is that a tripod minimizes the effects of handling the camera incorrectly or your own body movement. For static subjects, a tripod also allows for the use of smaller apertures for increased depth of field while allowing for slower shutter speeds that would be impossible to use if the camera were handheld.
You'll often discover a difference in image sharpness between photographs that are created with and without a tripod. Even at moderate shutter speeds, there can be a subtle but telling difference between such images, which becomes clearly evident when enlargements of 8x10 inches or larger are attempted. For optimal sharpness, try to use a tripod whenever possible.
3 Shutter Speed Considerations
The shutter speed used when shooting without a tripod plays a critical role in image sharpness. Choose too slow of a shutter speed, and the image reflects even the slightest camera vibration—even that of the shutter release being depressed. As a guideline, choose a minimum shutter speed that's the reciprocal of the focal length you're using. At an effective focal length of 100mm, select a minimum shutter speed of 1/125 sec., for example. At 200mm, raise the shutter speed to 1/250 sec. Be aware that some digital SLRs have a magnification factor that will increase the effective focal length of a lens, resulting in the need for an even faster shutter speed.
To maintain an acceptable shutter speed for handholding, you may need to increase the camera's ISO sensitivity or insert a faster-speed film. A film or digital camera with a low ISO of 50 or 100 may be insufficient and will require an ISO setting that's 400 or even higher. Although this increases the appearance of grain or noise, it can make the difference between a sharp image that you can use and a soft image that's useless.
With SLRs, the mirror movement within the body can result in adverse vibration. Usually at around 1/15 sec., the camera creates enough vibration to soften the image. Be careful using such shutter speeds even when the camera is mounted on a tripod. If that isn't possible and if your camera includes a mirror lockup feature, use it. The image in the viewfinder will be blackened, but the actual moment of exposure won't be impacted by mirror movement.
4 IS And VR
Some of today's lenses include technology that reduces the effects of camera motion on image sharpness—Canon's Image Stabilizer (IS) and Nikon's Vibration Reduction (VR). Available in a selection of lenses, these technologies use electronics and hardware to counter the slight lens movements that result in a soft image. These lenses have grown in popularity among sports and wildlife photographers, and although not intended to totally eliminate the use of a tripod, they provide a viable alternative when a tripod isn't practical or available.
These technologies offer the ability to handhold your camera at shutter speeds much slower than would be typically allowable. For example, a 200mm focal length that would normally require a shutter speed of 1/250 sec. may produce decent results at a shutter speed as slow as 1/60 sec. This is an advantage when light is fading and a higher ISO may not be advantageous or possible.
5 Continuous Shooting Mode
Most assume that the only time to use a camera's continuous shooting mode is when they're shooting fast action such as sports or wildlife. Actually, this mode can be used as a way to increase the sharpness of all your images.
With each depression of the shutter release button, there's a small degree of vibration that may adversely affect the crispness of your images. It occurs for only a fraction of a second, but it may be enough to produce undesirable softness. The use of a continuous shooting mode allows you to shoot several images of the same subject in rapid succession. Although the first image is slightly blurred because of vibration, subsequent images often will be sharper. Even for static subjects, you'll usually find one shot perfectly sharp among a group of softer images.
6 Confirming Autofocus
Autofocus has afforded a wonderful convenience for photographers. Its accuracy and responsiveness has improved the sharpness of many of our images. Particularly when photographing moving subjects, autofocus technology has made it possible to produce consistent results more often.
It's important not to totally surrender focus to this advanced technology, however. It's still necessary to confirm on what part of the scene is being focused. Multi-sensor autofocus systems, although accurate a majority of the time, may select another part of the scene that you don't want to emphasize. To ensure that your main subject is sharp, pay careful attention to the AF sensor indicators inside of your camera's viewfinder. The selected sensor will be different (depending on your camera). If the sensor isn't the one that you desire, set it manually.
When photographing moving subjects, begin tracking and focusing on your subject well before you actually release the shutter release button. This allows the camera to achieve focus before the critical moment you'll want to capture it.
7 Moderate Apertures
The rule of thumb for the aperture that results in the best sharpness on any lens has been two stops smaller than the widest aperture. A 105mm ƒ/2.8 lens likely will produce its best images at a working aperture of ƒ/5.6, for example. Computer-aided designs and advanced manufacturing techniques have improved lens performance throughout a lens' aperture range, but this is still a helpful guideline to follow.
Although fast lenses provide greater light-gathering capabilities (85mm ƒ/1.8, for instance), you should try to avoid using the lens at its maximum aperture. Even fast zooms, such as a 70-200mm ƒ/2.8, that deliver impeccable quality due to their aspheric and low-dispersion glass elements may not produce the best possible image at its widest aperture. To achieve moderate aperture under low light, either increase the ISO or introduce an electronic flash into the scene whenever possible.