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Reduction of Flare and Ghosting
The advanced optical design is optimized for digital SLR cameras. In addition, the new super coating on each glass surface produces superb color rendition, while reducing flare and ghosting.

SLD glass for superior optical performance
This lens uses four pieces of SLD (the special low dispersion) glass for excellent correction of color aberration throughout the entire zoom range.

HSM (Hyper Sonic Motor)
The HSM models (the HSM is only available for AF Canon, Nikon and Sigma Mounts) provide quiet high-speed AF function, as well as full time manual focus capability.

APO Tele-Converter EX (optional)
By adding an APO teleconverter (sold separately), you can use this lens as a 140-700ÇçÇç Çe7.3-8.8 MF ultra-telephoto zoom lens with a 1.4X EX teleconverter, or as a 200-1000mm F10.4-12.6 MF ultra-telephoto zoom lens with a 2X teleconverter.(Teleconverters can be used in 100mm – 500mm focal length range)

Easy Operation and Handling
This lens also features a Zoom Lock device to eliminate "Zoom Creep" when the lens is tilted down. When the lens is set to the 50mm focal length, it is remarkably compact and provides easy handling. The tripod mount is composed of magnesium, to minimize total weight and also it is easy to grip and carry the lens due to ergonomic design of the tripod mount.
Non-rotating front lens elements, due to rear focus mechanism make possible the use of a custom bayonet "Petal-type Hood", which prevents extraneous light from degrading the image quality. This mechanism also allows the use of circular polarizing filters, since the front barrel does not rotate during focusing or zooming.

Lens Construction: 20 Elements in 16 Groups
Angle of View: 46.8 - 5 degrees
Number of Diaphragm Blades: 9 Blades
Minimum Aperture: F22
Minimum Focusing Distance: 100-300cm /39.4-118.1 in.
Maximum Magnification: 1:5.2
Filter Size: Diameter 86mm
Dimensions: Diameter 95mm X Length 218.5mm 3.7 in. X 8.6 in.
Weight: 1,840g/64.9 oz.