Image Stabilizer (IS) dramatically reduces image blur caused by camera shake. Gyro sensors detect unwanted vibrations, triggering the corresponding movement of a correcting lens group perpendicular to the optical axis. This alters the light path, returning the image to its correct position on the sensor or film plane. The 3 stop advantage means that photographers normally shooting a 105mm lens handheld at 1/125 sec can obtain a shake free result with a shutter speed as low as 1/15 sec, for vastly extended options in low light conditions.
The ring-type USM motor found in the EF 24-105mm f/4L IS USM employs ultra-sonic frequency vibrations to drive auto focus with unrivalled speed and near-silent operation. A powerful CPU and improved AF algorithm contribute to speed performance. Good holding torque stops the lens with precision and accuracy, the instant it arrives at the correct focus point and without overshoot. Photographers can choose manual focus instantly and at any time simply by moving the manual focus ring without first having to switch out of auto focus mode. Circular aperture producing attractive background defocus Inner focusing, ring USM and new AF algorithms for fast and quiet autofocusing Manual focusing enabled even during AF mode (full-time mechanical manual focus) Only environmentally friendly lead-free glass used in lens construction Filter diameter 77 mm / Dimensions (dia x len)
