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In this video, I do a review of the Canon EF 400mm f/5.6L lens. This is a great super telephoto lens for bird photography. The image quality on this lens is superb, and the build quality is even more impressive. Made from solid metal, I’d feel safe carrying this in the woods in case I need to knock out a bear or two.

The major downsides are the aperture and lack of image stabilization (IS), which may or may not be deal breakers depending what you take photos of. Using a 400mm lens, the depth of field is really small, so I realistically probably wouldn’t use a lens at f/2.8 or even f/4 too often, unless the subject was far enough away. With aperture of f/5.6 at a distance of 6 feet on a full frame camera such as the Canon 6D, you get a depth of field of 0.2 inches. In metric, at 2 meters, you get a depth of field of 0.65 cm. An aperture of f/2.8 would half those depths of field, which would make it unusable for most situations.

As for lack of IS, if you’re doing bird photography at 1/2000 or faster shutter speeds, the images should be sharp with or without IS. If you plan on using this lens indoors in bad lighting conditions, though, prepare to use ISOs in the 12’800 to 102’400 and wishing your camera could go in the millions of ISO.

The lack of IS is much more an issue for video work, where I’ve had some success handholding it and applying the warp stabilizer in Adobe Premiere Pro. It doesn’t turn it into tripod-steady footage, but closer to steadycam footage, which is usually quite acceptable.

Using a teleconverter, though, the image quality dropped quite a bit, and the aperture of f/8 (1.4x) and f/11 (2x) disabled the autofocus on my Canon 6D camera, which made this lens quite harder to use. But used without any converters, the autofocus was fast and accurate.

Overall I quite enjoyed renting this lens, and I’m looking forward to comparing it to other similar lenses such as the Canon 100-400mm L and the Tamron 150-600mm lens. My guess is the zoom versions would be more versatile in parts because of the zoom, but also because of the image stabilization, but for image quality, I believe the 400mm f/5.6L would come out on top by a large margin.