The EF 500mm f/4L IS USM is a professional L series lens, that was designed to replace the EF 500mm f/4.5L USM. This lens is constructed with a metal body and mount, and with plastic extremities and switches. Features of this lens are: a wide rubber focus ring that is damped, a distance window with infrared index, the ability to limit the focus range from: 4.5m to infinity, 4.5m to 10m, and 10m to infinity, it also has a focus-preset mechanism, an image stabilizer that is effective up to two stops and is tripod sensing, an AF stop switch, and is weather sealed. An 8 blade, maximum aperture of f/4, gives this lens the ability to create depth of field effects. The optical construction of this lens contains 17 lens elements, including one fluorite lens element, and two UD Lens elements. This lens uses an inner focusing system, powered by a ring type USM motor. The front of the lens does not rotate nor extend when focusing. This lens is compatible with the Canon Extender EF teleconverters.
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