Canon EF 200-400mm f/4 IS USM Extender 1.4X review: does the performance justify the price?

By Kevin Carter - Tuesday June 25 2013

Lens Review
Introduction | Canon EF 200-400mm f/4 IS USM Extender 1.4X image quality evaluation | Canon EF 200-400mm f/4L USM Extender 1.4x vs prime telephoto equivalents | Conclusion

When compared against Canon’s recently introduced redesigned 300mm and 400mm f/2.8 super-telephotos without the extender in use, we can see just how good a performer the Canon EF 200-400mm f/4L IS USM Extender 1.4 really is. While it can’t quite match them in outright sharpness (it is very close at each focal length setting) the other metrics are equally low. In fact, the zoom lens has a less lateral chromatic aberration than either of the other two, though bear in mind the two primes are a stop faster at full-aperture.