Designed to extend a lenses focal length by a factor of 2x, the redesigned Canon EF 2.0X III Teleconverter delivers optical performance on par with the finest Canon super telephoto lenses. It features a built-in microcomputer for seamless communication among camera body, lens and extender, features careful lens placement and coatings to minimize ghosting, flare and chromatic aberration, and even has a new Fluorine coating that keeps soiling, smears, fingerprints to a minimum. Extender EF 2X III meets necessary standards in terms of rugged, dustproof and water-resistant construction, and should be in every professional's camera bag.
Nikon - AF-S Nikkor 85mm f/1.4G Classic Portrait Lens
Canon - EF 70-300mm f/4-5.6L IS USM Telephoto Lens