300mm ƒ2.8G ED-IF AF-S VR Nikkor

Sony DSLR-A100

Pentax K10D

HOW–TO

Image Stabilization

When you can’t or won’t use a tripod, these technologies steady your hand

There are two basic types of stabilization used in D-SLR systems today: lens-shift and sensor-shift. Each has its advantages.

Lens-Shift Stabilization

With lens-shift stabilization, sensors in the lens detect camera shake, then the system shifts a group of internal lens elements to counteract the motion and keep the image from moving on the image sensor (or film, as stabilizer lenses can be used on 35mm SLRs as well as D-SLRs). Because the image is stabilized before entering the camera, you see a stabilized image in the viewfinder, too. That’s a big advantage of lens-shift stabilization. Another advantage is that camera shake at longer focal lengths is more easily dealt with by moving lens elements than by moving the image sensor. The drawback is that you have to buy special stabilizer lenses, and stabilization might not be available in the focal length you want.

Canon, Nikon, Sigma and Leica offer stabilized lenses (see Table A). Canon’s stabilized lenses carry an IS (Image Stabilizer) designation, Nikon’s is VR (Vibration Reduction), Sigma’s is OS (Optical Stabilizer) and Leica’s is MEGA O.I.S. (Optical Image Stabilization). Canon’s IS lenses can be used only on Canon EOS SLRs. Nikon’s VR lenses can be used only on Nikon and Fujifilm SLRs. Sigma’s OS offerings are available in mounts for Canon, Nikon and Sigma SLRs. Leica’s current offering is a 14-50mm Four Thirds System lens that can be used on all Four Thirds System D-SLRs (which are offered by Leica, Olympus and Panasonic).

Sensor-Shift Stabilization

Sensor-shift stabilization moves the image sensor itself, instead of lens elements, to counteract the effects of camera shake during handheld shooting. The big advantage of this system is that it works with all system lenses, not just specific stabilizer lenses. The draw back is that only the recorded image is stabilized; the image you see in the viewfinder isn’t. Most sensor-shift cameras provide a viewfinder LED that indicates when and to what degree the stabilizer is working.

Konica Minolta’s pioneering Maxxum 7D and 5D sensor-shift D-SLRs are no longer in production, but Sony’s DSLR-A100, Pentax’s K100D and K10D, and Samsung’s GX-10 all currently offer sensor-shift stabilization.

Gyro Stabilizers

Canon EF 400mm ƒ4 DO IS USM

Panasonic Lumix DMC-F250

Samsung GX-10

It’s important to note that lens-shift and sensor-shift stabilization systems don’t prevent the camera from moving; rather, they compensate for the movement. There are also separate gyro-stabilizing units on the market that can be attached to cameras. These are even more effective than the built-in systems and can be used with any camera, but they add bulk and cost. Kenyon’s units contain two gyro wheels (to stabilize both pitch and yaw) that spin at more than 20,000 rpm (it takes them six to seven minutes to reach operating speed) and are very effective at stopping camera shake. These units can be used in conjunction with stabilizer lenses for maximum shake elimination.

How Effective Is Stabilization?

I’ve shot more than 150,000 images with Canon IS and Nikon VR lenses, plus several thousand more with sensor-shift cameras, and all the stabilizing systems I’ve used (Canon, Nikon, Pentax, Sony, Konica Minolta) have given me noticeably sharper images at all the shutter speeds I normally use.

Just how effective stabilization is depends on the lens focal length and shooting conditions, but I’ve found that, on average, these systems will provide equivalent results three shutter speeds slower than without stabilization. For example, if you can get sharp handheld results with a 300mm lens at 1⁄250 sec., you should be able to get equivalent results with that lens at a shutter speed of 1⁄30 sec. with stabilization. And that means you can shoot at lower ISO settings in a given light level for better image quality.

It’s worth noting that stabilization reduces the effects of camera movement, but it can’t do anything about subject movement. If your subject is moving, and you’re shooting at a slow shutter speed, there’s going to be some blur. You can use this creatively by panning the camera with the subject (to get a fairly sharp subject against a blurred background) or by locking the camera on a tripod so that stationary portions of the scene stay sharp while the moving portions blur.

Using Stabilized Gear

There’s no big trick to using lens-shift or sensor-shift stabilized gear. Just remember to switch the system on, and give it a second or so to do its thing before you fully depress the shutter button to make the exposure.

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