Designed to extend a lenses focal length by a factor of 2x, the redesigned Canon Extender EF 2X III 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.

Please keep in mind that using this Tele-Converter "costs" two stops of light, so your 70-200 f/2.8 will become a 140-400 f/5.6. Certain cameras have trouble auto-focusing at apertures beyond f/5.6, call us if you have any concerns.

Q & A

Does this teleconverter support autofocus?

• This teleconverter only supports autofocus if the effective maximum aperture of the lens and teleconverter combo does not exceed the limits of your chosen Canon camera. This teleconverter adds two stops, so f/2.8 becomes f/5.6, f/4 becomes f/8, etc. Check your manual or feel free to contact us to verify if autofocus will work.

Which lenses do you recommend for use with this teleconverter?

• If you rent this teleconverter and attempt to use it with any lens other than the ones listed under “Recommended Lenses,” there’s a chance it won’t work. If it does work, you very likely won’t be happy with the results.

Is this teleconverter incompatible with any lenses?

• The Canon 2x III will not fit on wide-angle zooms, standard zooms, wide-angle primes, and many third-party lenses.

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