Introduction

Canon EF 400mm f/5.6L USM is one of three 400mm primes Canon currently offers in its lineup of super telephoto lenses. This is the slowest 400mm prime, as well as the most affordable among the trio of 400mm Canon primes, priced at ~US$1,100 (as of October 2008). The lens was first released in mid 1993 and so far Canon has not yet announced any plans to replace this model with one that incorporates an IS system.

The optical construction of the lens consists of 7 elements in 6 groups, including one Super UD (Ultra low Dispersion), whose characteristics resemble fluorite, and one UD element. The optical formula follows an inner focusing design, which means that theinner cams of the lens do not extend during focusing, keeping the length of the lens constant at all times. The build quality of the lens is superb, as pretty much is the case for Canon's all L series of lenses - the barrel is metal, as is the built-in lens hood and the tripod collar, and the focus ring is fully rubberized. There is no wobbling inside or out and the lens looks and feels pretty sturdy. The lens is about average in length and weight when compared to other long telephoto lenses, measuring 90 x 256mm (3.5 x 10.1in) and weighing 1250g (2.8lb). Still. while the lens might be considered average in size when compared to super long telephotos, it is certainly not a compact one - with the built-in lens hood extended, the lens looks pretty monstrous, even on a Canon 5D.

The lens sports a fully electronic aperture mechanism, which means that there is no dedicated aperture ring and all aperture settings have to be controlled directly from the camera. The minimum focusing distance for the lens is 3.5m (11.5ft), but the lens also includes a focusing limiter switch that offers two modes: mode 1 allows focusing from 3.5m to infinity and mode 2 allows focusing from 8.5m to infinity. At its minimum focusing distance the lens will give you a 1:9 magnification ratio. Canon EF 400mm f/5.6L USM incorporates a USM type auto-focusing along with a fully manual focusing system. The focusing mode is controlled by an AF/MF switch located on the side of the barrel. The minimum aperture is f/32 and the lens accepts 77mm screw in type filters.

Image

 

The factory box includes Canon EF 400mm f/5.6L USM lens, front and rear lens caps, LP1222 semi-hard lens case, warranty and manual. The lens is compatible with Canon's EF 1.4x and 2x tele converters and EF 12 II and EF 25 II  extension tubes. The lens was designed for traditional 35mm cameras, so when used on APS-C cameras the field of view of the lens will be similar to that of a 460mm prime on a full frame body.

 

Summary
Lens Composition 7 elements in 6 groups
Angular Field ~6 degrees
Minimum Focus 3.5m/11.5ft
Focusing Action AF/MF, USM
f-stop Scale f/5.6-f/32, camera-controlled
Filter Size 77mm
Lens Hood Built-in
Weight 1250g/2.8lb
Dimensions 90x256.5mm/3.5x10.1"
Lens Case LP1222 (included)

 

Field Tests

Canon EF 400mm f/5.6L USM is a pretty long, albeit relatively narrow lens. Pop out the build in lens hood and you are guaranteed to gather some curious looks from passersby. It's certainly not the longest or the heaviest super telephoto lens out there, but at almost 1.3kg (~3lb), the hand-held photography with it is going to be somewhat unwieldy. You will obviously be better off if you are using auto-focusing, which is pretty fast and accurate in most situations (read: in good lightning conditions). However, if you plan to manual-focus the lens, then things will quickly get pretty complicated (here a good IS system would be quite useful) - rotating the wide focusing ring and at the same time holding a pretty heavy combination of camera/lens is going to take some practice. Hence most of users will probably be better off when using a tripod.

Overall, tThe lens showcased very solid resolving capabilities in the field. Images were quite sharp in the center, however, the lens seemed to produce somewhat softer results around borders when used on a full frame camera. The overall difference was pretty minor, and in many cases barely noticeable to the naked eye, so there is no reason to panic in my opinion. Most photographers would use some form of sharpening in post processing anyway, which should in most cases mask the somewhat weaker border resolution.

 

Left: ISO 500, 1/1000, f/5.6; Right: ISO 500, 1/500, f/8 (Canon 5D)
Left: ISO 500, 1/1000, f/5.6; Right: ISO 500, 1/500, f/8 (Canon 5D)

Canon EF 400mm f/5.6L USM showed pretty decent handling of flare, as can be seen from the shots above. With a strong direct light source positioned within, or close to the image frame (in the examples below, the sun was hitting the front element of the lens at about 35 degrees), the lens showed some minor reduction in contrast across the frame, but that was pretty much it. Even the contrast loss was pretty minimal at f/5.6 and smaller apertures like f/8 and f/11 did not feel much different.

 

Vignetting @ f/5.6 - full frame vs 1.6x crop (400mm)
Vignetting @ f/5.6 - full frame vs 1.6x crop (400mm)

The lens showed practically no vignetting on both APS-C as well as FF cameras straight from f/5.6. Not a major achievement though, considering that this is such a long lens with a pretty conservative (read slow) maximum aperture. In general, color handling was quite good. The lens did not show any major sign of color fringing, with both axial as well as longitudinal chromatic aberration seemingly under control. Images carried sufficient amount of contrast throughout the aperture ranges tested in the field, colors were well saturated, albeit the color palette was a bit on the warmer side, which is common for most Canon lenses.

 

ISO 500, 1/1250, f/5.6, 400mm (100% crop)
ISO 500, 1/1250, f/5.6, 400mm (100% crop)

 

Lab Tests

Please note that MTF50 results for APS-C and Full-Frame cameras as well as cameras from different manufacturers are not cross-comparable despite the same normalized [0:1] range used to report results for all types of cameras.

 

Canon APS-C: Canon EF 400mm f/5.6L USM demonstrated pretty good performance in the lab, with very balanced overall results across the picture frame and throughout the tested aperture range. Center as well as border image quality remained on a consistently high level - no major peaks or valleys, which by itselft is a very good characteristic in any lens. Canon EF 400mm f/5.6L USM is capable of producing outstanding 16in prints throughout the aperture range and decent 24in prints at f/11. Conclusion? Results are pretty solid - not necessarily the absolute best across all lenses, but good enough to make the lens a solid choice for most of us.

 

MTF50 (Line Width/Inch on the Print) @ 400mm
MTF50 (Line Width/Inch on the Print) @ 400mm

 

Normalized raw MTF50 @ 400mm
Normalized raw MTF50 @ 400mm

 

CA on the APS-C type camera was pretty minimal. Center CA did not exceed ~0.4px, while border CA did not exceeded ~0.65px. The good news is that CA drops even further with stopped apertures, reaching negligible levels by f/11.

 

Chromatic Aberration (APS-C) @ 400mm
Chromatic Aberration (APS-C) @ 400mm

Here are 100% crops, taken with an APS-C type Canon Digital Rebel XTi, comparing image borders at f/5.6 and f/8.

 

Image borders @ 400mm (100% crop): f/5.6 vs f/8
Image borders @ 400mm (100% crop): f/5.6 vs f/8

Canon FF: The lens continued to perform quite well even on a full frame Canon 5D. Center performance remained consistently very good straight from f/5.6. Border image quality did suffer a little bit at f/5.6, where the lens performance is kind of average. But, once stopped down to f/8, border performance catches up and remains quite solid through the rest of the tested aperture settings. Conclusion? Very decent performance by all standards.

 

Normalized raw MTF50 @ 400mm
Normalized raw MTF50 @ 400mm

 

The lens showed negligible amount of barrel distortion - at ~0.29%, distortion should not be visible in general type photography, which is not that surprising for such a long telephoto prime.

 

Distortion (FF) @ 400mm
Distortion (FF) @ 400mm

The amount of chromatic aberration on a full frame Canon 5D was pretty minimal. Center CA hovered ~0.3px, while border CA averaged ~0.5px, all across the tested aperture range. Nothing to worry about here.

 

Chromatic Aberration (FF) @ 400mm
Chromatic Aberration (FF) @ 400mm

Here are 100% crops, taken with a FF type Canon 5D, comparing image borders at f/5.6 and f/8.

 

Image borders @ 400mm (100% crop): f/5.6 vs f/8
Image borders @ 400mm (100% crop): f/5.6 vs f/8

 

Alternatives

As mentioned earlier, Canon currently offers two other 400mm primes in its lineup - the top of the line EF 400mm f/2.8L IS USM and the mid-range EF 400mm f/4 DO IS USM. Both lenses offer excellent performance characteristics, but cost 3 to 5 times more then the EF 400mm f/5.6L USM lens reviewed here. Other long telephoto primes that are worth considering include the usual suspects from Canon - EF 300mm f/2.8L IS USM, EF 300mm f/4L IS USM (as well as its older, now discontinued non-IS version) and EF 500mm f/4L IS USM, as well as a couple of lenses from 3rd party manufacturers, including Sigma's APO 300mm f/2.8 EX DG HSM and Tamron's SP AF 300mm f/2.8 LD IF. If you are willing to entertain the idea of adapting and using a non EF mount lens, then Nikon's superb Nikkor 300mm f/2.8D ED IF (discontinued and replaced with an aperture-less G version, which is not that easy to adapt to any ohter camera) should remain on your list of options.

 

Recommendation

Canon EF 400mm f/5.6L USM is an excellent long telephoto prime that should be considered by anyone with a limited (relatively speaking) budget. The lens offers very solid image quality and excellent build quality, with good handling of various artifacts, including flare, vignetting and color fringing, all at a more or less affordable price. Are there better super long telephotos out there? Sure. However, all of the better lenses also would cost 2x-3x of the EF 400mm f/5.6L USM reviewed here. Short of the somewhat slow maximum aperture, EF 400mm f/5.6L USM would satisfy the needs of most casual as well as semi-pro photographers.