EF 100-400mm f4.5-5.6L IS USM

introduced 1999

The fourth Canon EF lens to incorporate Canon's unique Optical Image Stabilising technology, which reduces the effects of camera shake without affecting image quality. IS gives the effect of using a shutter speed two stops faster (1.5 stops at the wide-angle end), making the lens usable in low-light conditions and situations where a tripod cannot be set up. A Ring USM is used to drive the autofocusing system, giving near-silent high-speed operation.

Full manual focus is possible in the autofocus mode for fine adjustments. High image quality is ensured by the use of fluorite and Super-UD lens elements which correct secondary chromatic aberrations. This is the first EF lens to have both rear focusing and a floating system to provide high image quality at all focal lengths. The lens can be used with EF 1.4x and 2x Extenders. Centre point focusing is possible when the lens is used with the EOS 3 and EF 1.4x Extender.

Focal length and maximum aperture: 100-400mm 1:4.5-5.6
Lens construction: 17 elements in 14 groups
Diagonal angle-of-view: 24°-6°10'
Focus adjustment: ring type USM, rear focusing system, full-time manual focus
Closest focusing distance: 1.8 m/ 5.9 ft., 0.2 x magnification
Zoom system: linear
Filter size: 77mm
Max. diameter x length, weight: 92 x 189mm, 1,380g