Canon EOS Rebel T3i 18-135mm IS Lens Kit EOS System Brochure 2011 - Page 15
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Image Stabilization: It Belongs In the Lens EF LENSES EF LENS TECHNOLOGY Great images start with great lenses and, in many ways, an SLR is defined by the quality, breadth and scope of its associated system of lenses. For many, Canon EF series lenses alone are reason enough to choose the EOS System. A blend of some of the world's most advanced optical, microelectronic, and precision manufacturing technologies, EF lenses are perfected in Canon's laboratories and proven in the field. Whatever you shoot, whatever your budget, there are Canon EF lenses perfect for your needs. Optical Image Stabilizer Canon Optical Image Stabilizer technology makes handheld photography more practical at slow shutter speeds, accommodating more low-light shooting situations than ever before. Camera shake typically occurs at shutter speeds less than 1/ [focal length], resulting in image blur. Canon Optical Image Stabilizer technology uses miniature sensors and a high-speed microcom- puter built into the lens. The sensors analyze vibrations and apply correction via a special stabilizing lens group that shifts the image parallel to the focal plane. Motion blur is ©Arthur Morris Image Stabilizer OFF Image Stabilizer ON canceled, resulting in a sharper image. With Optical Image Stabilization, it's like gaining up to four stops. Canon Optical Image Stabilizer technology is built into many EF or EF-S lenses and outperforms in- camera stabilization technologies found in other cameras by allowing for more movement of the stabilizing lens group. Especially with telephoto lenses, as the lens focal length increases, the effect of shake and the degree of correction needed to cancel it increase as well. With the Optical Image Stabilizer in the lens, Canon can equip each IS lens with a stabilization unit optimized for the focal lengths and optical characteristics unique to that lens Other systems are limited by how far they can move an image sensor, and as a result their stabi- lization is less effective as telephoto lengths get longer. Also, the result of Optical Image Stabilization can be seen right in the viewfinder- impossible with some other stabilizer systems. Optical Image Stabilizer Parallel Movement Principle Because every lens is different, different lenses have different Optical Image Stabilizer needs. • Reduces motion blur by counteracting camera shake during handheld photography • With Optical Image Stabilizer in the lens, Canon can equip each Optical Image Stabilizer lens with the stabilizer it needs • Found on some telephoto lenses, Optical Image Stabilizer Mode 2 is especially effective when doing panned shots • With Canon Optical Image Stabilizer, the effects of the stabilization can be seen in the viewfinder-the image is steadier, making composition more accurate How the Image Stabilizer Works - The Optical Image Stabilizer shifts a lens group in parallel to the focal plane. When the lens jerks due to camera shake, the light rays from the subject are bent relative to the optical axis, resulting in a blurred image. Camera shake is detected by two gyro sensors (one each for the yaw and pitch). The gyro sensors detect the angle and speed of the camera shake caused by handheld shooting. By moving select lens elements according to how the entire lens is being shaken, the image passing through the lens can be steady and sharp when it hits the imaging sensor. The figure on the right shows what happens when the lens is jerked downward. The center of the image moves downward on the focal plane. When the Optical Image Stabilizer lens group shifts downward, the light rays are refracted so that the image center returns to the center of the focal plane. Since Optical Image Stabilizer Units image shake occurs in both the horizontal and vertical directions, the Optical Image Stabilizer lens group can shift vertically and horizontally on a plane perpendicular to the optical axis to counteract the image shake. Optical Image Stabilizer in effect, right in the viewfinder. 1: No Camera Shake 2: Lens Front Shake Downward Camera Shake 3: Image-stabilizing group counteracting downward camera shake Close-up - For close-up shots, even the tiniest of motions is magnified and spoils a great shot! Low-light - In low light situations, when you would normally expect to have to use flash or tripod, Canon's Optical Image Stabilizer lenses give you the freedom of up to 4 stops of light. Telephoto - Canon designs each Optical Image Stabilizer system to complement the lens' focal length. So even with telephoto lenses you'll capture the shot! 31