Image Stabilized Binoculars  

The Quest For "Power"

While it may go against tradition, optically savvy observers never try to use a binocular or telescope at magnifications higher than those required to do the job at hand. Why? Because although higher magnifications may offer increased resolution the disadvantages of exceeding practical limits always outweigh advantages.

When magnification is increased:

* Image brightness is decreased because a finite amount of light is spread over a greater area,
* The field of view decreases (making objects harder to find and keep centered),
* Atmospheric disturbances are accentuated, and
* Vibrations may become annoying (you may need a tripod).

This is true for all telescopes and binoculars. Fortunately, even the most "powerful" binoculars offer magnifications considerably lower than those expected of even a low-power telescope. Thus, of the four concerns above, only vibration remains in problem in most binoculars.

So, what does one do who wants a steady, highly magnified image without the aid of a tripod? They turn to image stabilized (IS) binoculars.

Fujinon

Fujinon introduced the first image stabilized binocular-the Stabiscope-in 1980. This robust, waterproof binocular went unchallenged for many years and, for the most demanding work, remains unchallenged. Images in the Stabiscope are steadied by the use of a high-speed gyro attached to internal chases that hold the optics. Using this technology, an image at 14-power may be stabilized enough for use from a helicopter, fast moving boat or automobile.
 
The Stabiscope is heavier and more bulky than conventional binoculars-even those with considerably larger apertures. This, added to a price tag reading $4,000 or more, has kept it from catching on with most casual observers.

In 1990, the legendary Carl Zeiss firm introduced its 20x60S binocular, the first binocular to achieve stabilization through a mechanical "dampened stabilization mechanism" that does not rely on electronics. Based on mechanical principles alone, the 20x60S does not dampen as thoroughly as the Stabiscope. Some observers state that they feel the vibration in the 20x60S is reduced to that which one might expect from a 4-power binocular-or about half of that experienced in using a traditional 7x50. This is pretty impressive considering that, at 20-power, it has more "jitters" to suppress than any other IS binocular yet introduced. Still, it is noticeably longer than the Stabiscope and not a great deal more ergonomic. One appreciable feature is that, not requiring any electronic components, it is ready to go at all times, and one need not worry about a battery pack going out at a critical moment. 

Surf the web for information on image stabilized binoculars and it would be easy to come away with the notion that Canon models were first on the scene-in fact, they were third.