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By Allan Weitz


If you enjoy taking pictures, professionally or simply of family and friends, sporting events, or other occasions where you just enjoy taking pictures, chances are you use a digital camera. And if you do not use a camera, a box of donuts says you were running around taking pictures with your cell phone.



Canon 15x50 IS binoculars
Anti-shake technology first appeared in binoculars and video cameras
 

Not all that long ago that last sentence would have sounded like pure science fiction. Not any longer. Times have changed and they continue to change quickly.

One of the ways camera manufacturers have been enabling us to take sharper, clearer pictures is by incorporating technologies that help to eliminate camera shake.

Anti-shake technology has been around for quite some time. It first appeared on the consumer market in the form of binoculars and video cameras. The technology worked as promised. Jumpy images of Junior riding his bike into the garage door and cock-eyed horizon lines became less frequent in our home videos.

Advanced versions of IS technology quickly found their way into Canon lenses for the popular Canon EOS film and digital cameras. Canon's IS-series lenses and Nikon's VR-series lenses make it possible to handhold SLR & DSLR cameras at shutter-speeds of up to three-stops slower than normally recommended.

 

Lenses with anti-shake technology:
 
Canon 24-105/4 L IS Canon 70-300/4-5.6 IS Nikon 70-200/2.8 AF-S VR


A long-accepted rule of thumb is you should never handhold any lens at a shutter-speed slower than the focal length of the lens on your camera. If you are using a 200mm telephoto lens, this works out to 1/200th of a second. A 20mm wide-angle lens should be handheld at no less than 1/20th of a second. A 1000mm lens should be used at nothing less than 1/1000th of a second.

A 200mm lens enhanced with IS technology, on the other hand, can be handheld at shutter speeds as low as 1/25th of a second, while a 20mm IS lens can be handheld as low a half-second. A 1000mm lens? How about 1/125th of a second. If your plans include photographing Red-Tailed Hawks at dusk with a long lens this technology is well worth the extra expense.

How Image Stabilization technology works is as interesting as it is complex. Both Canon IS (Image Stabilization) series lenses and Nikon VR (Vibration Reduction) series lenses utilize a "floating" lens element that is controlled by small, microprocessor-driven motors. These electronically controlled motors shift the lens element about in response to any motion that is detected whenever the auto-focus system is engaged.

As motion is detected, the microprocessors shift the floating element in the opposite direction of the subject's movement. If there is a slight shift to the right, the lens element shifts slightly to the left. As the subject shifts up, down, left, right, or diagonally within the frame, the lens element shifts the exact amount in the opposite direction. By enabling this floating element to "fix" the image on the same point on the film or sensor, sharp pictures can be captured at shutter speeds that used to be considered rather dicey.

The latest generation of anti-shake lenses work equally well for stationary subjects as well as subjects that require panning action such as sporting events and chasing 5-year olds.

Though many variable aperture zoom lenses in the slower 3.5 - 5.6 f/stop range incorporate anti-shake technology as a means of making "slower" lenses practical to use under low light conditions, both Nikon and Canon also offer anti-shake technology in their faster 70-200/2.8 AF lenses.

While you might think it's not necessary to smooth out the action when using faster lenses outdoors, the higher resolution imaging sensors found in top-of-the-line DSLR cameras from Nikon and Canon have added a new wrinkle into the mix, namely the fact they are sharper than their film-based SLR counterparts

The newest generation DSLRs such as Nikon's D200 and D2x, and especially Canonís full-frame EOS 5D and EOS 1Ds, have pushed the resolving power of the best lenses these manufacturers have to offer.

Even though Canon manufactures over 50 lenses, they only recommend about a dozen of them for use on Canon's full-frame DSLRs. On film cameras, all of Canon's EF lenses work well. On the EOS 5D and EOS 1Ds however, Canon strongly recommends you stick to their "L"-series and macro lenses if you plan on producing large prints from your image files.

The same holds true for pictures taken with the higher resolution, APS-sized chips found in Nikon's D200 and D2x.


The bottom line is if you want to get your money's worth from any of the current high-end DSLRs, think twice about your choice of lenses.

Many digital point-and-shoot cameras are also incorporating anti-shake technologies to help insure sharp pictures. Smaller cameras in particular are prone to shaky images because we tend to compose our photographs while holding our cameras out at arms length. Conversely, when we take pictures with SLR-type cameras we usually tuck our elbows tightly to our body, which steadies our grip on the camera. Not so with our trusty point-and-shoots.

Konica-Minolta was the first to incorporate anti-shake technology in the form of "digital" image stabilization. Rather than shifting a lens element around to smooth out the action, digital image stabilization shifts the imaging sensor back-and-forth. Sony currently utilizes similar technology in several of their own cameras.

While optical and digital technologies achieve the same goal, there is often a slight loss of image sharpness in pictures taken with digital stabilization technology due to the mechanics of the process. At the end of the day the "softer" pictures you get from the digitally stabilized cameras are still sharper than the images you get from their non-stabilized counterparts.

 

Casio Exilim-series point-and-shoot camera's currently offer digital stabilization in it the 5 to 7-megapixel range.
Casio Exilim EX-S500
Panasonic's new Lumix DMC-T21 digital point-and-shoot has broken the mold by incorporating optical image stabilization into the camera's Leica DC Vario-Elmarit 10x (optical) zoom lens. This camera should be shipping shortly and should prove to be a honey.
Lumix DMC-T21


As for cell phones, NTT Kyocera recently announced a 3.3-megapixel cell phone that offers yet a third type of anti-shake technology. Rather than juggling lens elements or imaging sensors, the Kyocera NTT N902i captures a quick burst of images each time you take a picture and synthesizes these images into a single sharp image.

Science fiction isn't what it used to be - is it?
 

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