- L type telephoto zoom lens
- 4-stop Image Stabilizer for blur-free shots
- Five UD lens elements help to drastically reduce chromatic aberration
- Robust build with superb handling
- Close focusing distance of 1.2m (3.9ft)
- Ring-type USM with high-speed CPU for silent, high-speed AF
The lens’ constant f/2.8 maximum aperture means that no matter what focal length you choose within the zoom range, you’ll get great low light performance and the ability to capture what available light there is. The large maximum aperture means that even using an EF1.4x II or EF2x II extender (for a 98-280mm f/4 or 140-400mm f/5.6 lens) in both cases all AF points in the camera will still function and autofocus will still function no matter which EOS camera you use.
The lens’ ring-type USM autofocus motor combines with a new high-speed Central Processing Unit (CPU) and an optimised AF algorithm to make autofocusing both faster and quieter than that of its predecessor. The lens’ AF system perfectly matches the AF abilities of the EOS-1D Mark IV and EOS 7D DSLRs. Compared to its predecessor the lens’ updated Image Stabilizer adds an extra stop of IS capability, so you can shoot hand held for a shutter speed advantage of up to four stops.
The re-designed optical system in the lens features 23 elements in 19 groups to deliver truly impressive results. A high-performance fluorite element is used at the heart of the lens path with five ultra-low dispersion (UD) lens elements to drastically reduce chromatic aberrations throughout the zoom range to produce sharp, high contrast images with edge-to-edge definition.
As many photographers will use this as a 'workhorse' lens the build quality has been upgraded. The thickness of protruding external parts has been significantly reduced to guard against accidental switching and the rubber, focusing grip has been re-designed and widened with finely-patterned grooves, making it easier to manually focus. The robust, durable lens is fully weatherproof and the mount, focus mode switch and focusing ring all have a dust and drip-proof structure to prevent any dust or water from getting inside the camera and lens when used with accompanying weatherproof EOS SLR bodies.
A ring-type USM autofocus motor, combined with a new high-speed CPU and an optimised AF algorithm, delivers fast and near-silent AF with precision. It also provides full-time manual focus so that you can adjust the focus with the focus ring, without first having to switch the lens to manual focus. This allows you to adjust the focus accurately to ensure it is exactly where you want it to be for the most creative control possible.
The Image Stabilizer in a Canon lens works by shifting a stabilizer group of elements to compensate for motion detected by a gyroscope in the lens. There are two IS modes – Mode 1 for general shooting and Mode 2 for panning. This lens has an Image Stabilizer that gives up the equivalent of four stops of shutter speed so you can hand hold and capture acceptably sharp images.