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Tuesday, May 26, 2009

Time For An Upgrade

With so many recent advancements in optics technology, is now the time to revamp your collection of lenses?

This Article Features Photo Zoom

Fast Aperture For APS-C Format Designed specifically for Nikon’s DX-format (APS-C) D-SLRs, the AF-S DX Zoom-Nikkor 17-55mm ƒ/2.8G features three ED elements and three aspherical elements to minimize aberrations and distortion and maximize image quality. The Silent Wave AF motor provides quick, quiet autofocusing with all Nikon D-SLRs and permits fine-tuning focus manually without leaving AF mode.

It’s also important to note that many smaller-sensor lenses aren’t pro lenses. Many Canon and Nikon pros have sold superb images shot with Canon and Nikon D-SLRs and pro lenses that were designed for 35mm SLRs. An excellent pro lens is an excellent pro lens, regardless of format. Where the designed-for-digital lenses shine is in the lower-priced category. A low-priced, designed-for-digital lens will perform better on a small-sensor D-SLR than a similarly priced full-frame lens. But most pros use the pro lenses, which can produce excellent images with all cameras they fit.

That said, the more recent pro lenses were designed with digital imaging in mind. For example, Canon’s EF 16-35mm ƒ/2.8L II USM pro ultrawide zoom employs a lens configuration and coating designed to minimize flare and ghosting due to reflections from the sensor-assembly surface, three types of aspherical elements to improve peripheral quality at wide angles and two UD elements to minimize the chromatic aberrations inherent in wide-angle lenses. Performance is excellent with all Canon D-SLRs, even though it’s not an EF-S “small-sensor” lens. Conversely, some small-sensor lenses do meet pro specs: While not pro L-series lenses (due to a policy that L-series lenses cover a 24x36mm format at infinity), Canon’s EF-S 17-55mm ƒ/2.8 IS USM and EF-S 10-22mm ƒ/3.5-4.5 USM do employ “exotic” glass aspherical and UD elements like the L-series.

Autofocusing
Not all AF lenses are created equal. Canon USM, Nikon AF-S, Olympus SWD, Pentax SDM and Sigma HSM lenses employ built-in ultrasonic focusing motors that provide quick, smooth and near-silent operation. If you shoot action or if camera noise is a consideration, you’ll want to use these efficient, quiet lenses. (When one of these lenses is used on a camera body that has a focusing motor, the motor in the lens is used.) Bear in mind that maximum sharpness for nonmoving subjects will occur with a tripod-mounted camera and the lens focused manually. Handhold-ing the camera, or using AF, will reduce sharpness.

Next-generation AF lenses perform better with next-generation D-SLRs, and top-of-the-line lenses autofocus more quickly and accurately than lesser lenses from the same manufacturer. So if you shoot action, or rely on autofocusing for general shooting, now is a good time to upgrade.

Made For APS-C Format The Carl Zeiss Vario-Sonnar T* DT 16-80mm ƒ/3.5-4.5 was designed specifically for Sony’s APS-C D-SLRs (i.e., all but the full-frame A900). Equivalent to a 24-120mm zoom on a 35mm camera, it weighs just 16 ounces, can focus down to 14.4 inches and features two aspherical elements to control aberrations and distortion.

Stabilization
If you work handheld, you’ll love stabilized lenses. Canon IS, Nikon VR, Sigma OS, Tamron VC and Panasonic MEGA O.I.S. systems all are effective, allowing one to get sharp handheld shots two to four shutter speeds slower than is possible without stabilization. But be warned: Stabilization is habit-forming—once you get used to it, you’ll find it hard to work without it!

Newer stabilized lenses have more effective stabilizers than previous generations. My first stabilized lens provided two-stop stabilization (I can shoot handheld two shutter speeds slower with stabilization than I could without it). Today’s stabilizer systems are good for four or more stops. So if you work handheld and don’t have stabilized lenses (or have first-generation stabilized lenses), an up-grade could make a big difference. Only Canon, Nikon, Panasonic/Leica, Sigma and Tamron currently offer stabilized lenses. Olympus, Pen-tax, Samsung and Sony offer D-SLRs with built-in sensor-shift stabilization.

So, Is It Time?
Your pro lenses should work well with your D-SLR, whether they were designed for 35mm SLRs or for digital SLRs. But most newer lenses have been designed for digital imaging and will produce better results. And the newer lenses also employ the latest lens technologies, which also lead to better images. So if you’re thinking of upgrading your old film lenses or just would like a new focal length, now is a great time to do it.