Light heavyweight: Canon EF 400mm f/2.8L IS III USM

With a listed sales price of over € 13,000.00, the Canon EF 400mm f/2.8L IS III USM is not a lens that will find its way into everyone’s bag. It is one, though, stock in trade for sports and nature photographers. The lens is easy to combine with the EF 1.4x III and EF 2.0x III teleconverters. That gives a 560 mm f/4 and an 800 mm f/5.6. And with that, you can also work well in terms of brightness, and the depth of field, thanks to the large focal lengths, is still limited, and the bokeh is very beautiful. Teleconverters not only increase the focal length of the lens with which they are used, but also their lens errors. If you use them with a lens that is almost perfect, then the result in combination with the converter is still very good. And that is the case with Canon’s super telephotos. There was actually nothing to criticize about the optical quality. The series II was already very sharp and free of chromatic aberrations. Where Canon has managed to make a profit is in the image stabilization, which should now effectively be five stops instead of 3.5 and especially the weight. The Canon EF 400 mm f/2.8L IS III USM weighs only 2840 grams, which is one kilo and ten grams less than the previous model and almost half what version I weighed. Those are big differences. At 2840 g, the Canon also (just barely) dethrones the new 400 mm f/2.8 from Sony as the lightest super telephoto. For photographers who have to use this lens out of hand for a long time, e.g. sports competitions, observation in nature or air shows, more than a kilo makes a big difference. Perhaps less important is that the shortest setting distance has been reduced from 2.7 to 2.5 meters, but every little bit helps.

BUILD AND autofocus

This Canon EF 400 mm f/2.8L IS III USM looks very similar at first glance to its predecessor, the version II. But appearances are deceiving. The lens is completely new, not only on the outside, but also on the inside. The optical design is different, with a completely different arrangement of the lens elements. What is striking is that this version III actually only has a large front lens and that the other glass parts are much smaller and are much further back. This not only ensures less weight, but also a much better weight distribution than with the previous 400mms. The new EF 400mm f/2.8L IS III USM is therefore in much better balance with a camera. It is easier to support this lens because the center of gravity is not so far forward, and that makes working with the EF 400 mm f/2.8L IS III USM much nicer. Because of the different layout, both the autofocus mechanism and the aperture for this lens also had to be newly designed. The aperture is now further forward and is larger than on previous models. It consists of 9 lamellae. The lens is completely sealed against dust and moisture and, besides Canon’s SSC and ASC coatings, there is also a fluorine coating on the front lens, making it easier to keep it clean.

The autofocus is an important part of the performance of a lens like this, which will be used for many fast-moving subjects such as athletes and birds. The Canon EF 400 mm f/2.8L IS III USM has a few special features. For example, three different speeds can be chosen for the focus ring. This allows you to choose between slow and very precise setting or making quick adjustments over longer distances. Also, two focus points can be quickly pre-programmed so that you can go directly to them when necessary. The shortest setting distance of the Canon EF 400mm f/2.8L IS III USM is 2.5m. That is quite good for a long telephoto.

IMAGE QUALITY

You expect nothing more or less than optical perfection from a lens with a price tag like that of the Canon EF 400 mm f/2.8 L IS III USM. The previous generation was already incredibly good, so we are not satisfied with less. The test results speak for themselves. This 400mm scores just as well at full aperture as stopped down one or two stops, and the corners don’t lag behind the center. You can’t get any better. Chromatic aberrations are also not perceptible, and that makes for a very nice, clean image. That also gives this lens a good basis for use with teleconverters. They magnify the lens errors of the lens with which they are used. And if that lens is as good as this Canon EF 400mm f/2.8L IS III USM, then there is little to magnify errors, and the image you get with the teleconverters should also be unusually good.

 VIGNETTING AND DISTORTION

If the Canon EF 400mm f/2.8L IS III USM shows any weakness, then it’s the vignetting at full aperture. With more than 1.8 stops, that is pretty high. That’s not terribly surprising, because f/2.8 is pretty bright for a 400mm, and bright lenses generally have little trouble with vignetting. Of course, a bit of vignetting is not really bad. Many photographers even like it because it draws attention to the center of the shot. And if you do find it annoying, then it is easy to correct in post-processing (at the cost of a bit of dynamic range in the corners), or you can prevent it by simply by stopping down two stops to f/5.6, and then it is hardly measurable and certainly not visible anymore.

Some distortion is also visible with the Canon EF 400mm f/2.8L IS III USM, but then you have to look very carefully, since less than half a percent pincushion distortion is not much. In sports and nature photography, you will never really see it. You might only notice for things like architecture and reproductions (but who uses a lens like this for that now?). If you’re bothered by it, it’s easy to correct in post-processing with a negligible loss of image quality. 

Click here for sample images in full resolution.

Bokeh AND IMAGE STABILIZATION

The Canon EF 400mm f/2.8L IS III USM obviously has built-in image stabilization, and, according to Canon, this should be good for about 5 stops’ improvement. When testing in low light, we did indeed notice that you can get close to that in practice. That ensures that you can continue to work by hand with this lens even under less-than-ideal circumstances. This Canon EF 400 mm f/2.8L IS III USM also scores very well on another point: At full aperture, the background blur is as soft as you could wish for, without hard lines along twigs or highlights. Green and magenta color edges that you see with less-good lenses at full aperture along blurred areas in the foreground and background are also almost entirely absent on this 400mm. 

ConclusiON: REVIEW Canon EF 400mm f/2.8L IS III USM @ Canon 5DsR

PROS

• Nice and light (for a 400mm f/2.8)
• Outstanding image quality
• Solidly built
• Good image stabilization
• Fast autofocus
• Beautiful bokeh

CONS

• Hefty, but not unreasonable, price
• Some vignetting at full aperture