Is the canon ef 200 400mm f 4l is usm extender 1 4x worth buying used?

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From Canon EF 200-400mm f/4L IS USM Extender 1.4x: Canon EF 200-400mm f/4L IS USM Extender 1.4x: A zoom lens by Canon for Full frame cameras, 200-400mm f/4. A professional wildlife zoom with a built-in 1.4x teleconverter. Specs - Maker: Canon - Focal length: 200-400mm (zoom) - Maximum aperture: f/4 - Made for: Full frame sensors - Mounts: Canon EF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon EF): as marked, 200-400mm. - On APS-C (Canon) (Canon EF): like 320-640mm ...

From Wildlife and sport: My picks: - Starting out: an APS-C mirrorless body with a 100-400mm-class zoom. The best value reach there is. - Hiking and travel wildlife: Micro Four Thirds with a 100-400mm. Light, long and stabilised. - Serious sport and birds: a full-frame body with fast readout and a 200-600mm or 150-600mm zoom. Buy used: long lenses hold their value and change hands a lot, and the savings are large. See buying used.

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