Canon EF 200-400mm f/4L IS USM Extender 1.4X is an ideal lens for air shows, where aircraft rapidly move from distant to close, where fast autofocus is necessary, and where sharp optics can capture great detail. This is a Russian jet, a Sukhoi Su-35, at the Paris Air Show in 2013.
Even relatively bold birds such as this blackbird are small and twitchy, so photographers will need every bit of focal length and aperture. The Canon EF 200-400mm f/4L IS USM Extender 1.4X, at 8.3 pounds, isn't easy to move quickly to track fast-moving birds, but its 560mm f5.6 option, image stabilization, and sharpness are big assets for wildlife photography.
Usually a long zoom range means compromised optical performance, but the built-in 1.4x extender in Canon's EF 200-400mm f/4L IS USM Extender 1.4X gives it a great range and great image quality, albeit at a sky-high $11,799 price. These photos show a Paris restaurant in the foreground and a La Defense skyscraper in the background. At the top is 200mm, in the middle is 560mm, and at the bottom is 400mm.
Canon EF 200-400mm f/4L IS USM Extender 1.4X can be moved rapidly from 200mm to 560mm by flipping the 1.4x extender lever and rotating the zoom ring, something that's handy as air show planes come and go. See the next image for a look at the sharpness of the planes.
This 100 percent crop from the previous gallery image shows crisp words on the aircraft. This shot with the Canon EF 200-400mm f/4L IS USM Extender 1.4X was taken at 225mm, f4, 1/2,500 sec., at ISO 400.
Chromatic aberration is only a sliver of a problem on the Canon EF 200-400mm f/4L IS USM Extender 1.4X, showing only in high-contrast scenes and requiring pixel peeping to even see much of the time. These 100 percent crops of a Boeing 787 Dreamliner's tail (to the lower left on the bottom image) show the slight chromatic aberration in the top image and Adobe Lightroom's corrections in the center.
With an extra 1.4x telephoto extender attached, the Canon EF 200-400mm f/4L IS USM Extender 1.4X reaches to 784mm with an f8 aperture that was nice for shooting the 2013 supermoon. This photo was shot with Canon's second-generation 1.4x extender, but Canon recommends the third-generation model. I noticed some chromatic aberration issues and somewhat reduced sharpness with my equipment, with a blue fringe at the top of the moon visible in this cropped image.
Many supertelephoto shots feature a central subject, meaning that sharpness in the corners of the frame isn't as important, but this graffiti photo taken with the Canon EF 200-400mm f/4L IS USM Extender 1.4X was terrifically crisp corner to corner.