The world's first interchangeable lens with a built-in image Stabilizer (IS), the new Canon EF 75-300mm f/4-5.6 IS USM lens - designed exclusively for Canon EOS cameras, dramatically reduces the chance of a blurred photograph due to camera motion ("shake") especially when shooting at long focal lengths with slow shutter speed. Controlled by a built-in 16-bit microcomputer, a series of gyro sensors and micro-motors instantly shift one of the lens groups to compensate for inadvertent camera motion. A very practical benefit of the IS system is a reduction in the old "focal length = shutter speed" rule by two full stops. Now you can expect sharp pictures at 200 mm with a shutter speed of only 1/60th second!