Canon EF 400mm f/4 DO IS USM

• Specifications
• Reviews
• Sample Images
• Initial launch information.

Very short lens and lightweight for its focal length. The green ring signifies diffractive optics. Despite being announced with much hype, Canon has gone quiet on DO technology of late [2013].

The DO elements can be prone to producing odd OOF results for point light sources and gives somewhat lower contrast than non-DO lenses.

Available from: Amazon.com | Amazon.co.uk | B&H | Adorama

Lens specifications

Focal Length & Maximum Aperture	400mm 1.4
Lens Construction	17 elements in 13 groups
Diagonal Angle of View	6° 10'
Focus Adjustment	Inner focusing system with USM
Closest Focusing Distance	3.5m / 11.5 ft.
Filter Size	52mm Drop-In
Max. Diameter x Length, Weight	5.0" x 9.2", 4.3 lbs. / 128.0 x 232.7mm, 1940g

A quick guide to MTF charts (which only measure contrast and resolution. Canon's guide to their MTF charts) Black lines reflect lens performance at widest aperture. Blue lines show the performance at f/8 Thick lines indicate lens contrast Thin lines indicate lens resolution Dashed lines: Lens performance with meridional lines. Solid lines: Lens performance with sagittal lines Closer sagittal and meridional chart lines indicate more 'natural' out of focus areas. Remember that MTF charts are good for comparing similar lenses, so comparing ones from the 14mm f2.8L and 300mm 2.8L won't tell you much at all, whilst comparing the EF14 2.8L with the EF14 2.8L II will show meaningful differences. Note that other manufacturers may have different ways of displaying such information that may or may not match up with the Canon figures.

Which 400mm? - a list of all versions

Canon EF 400mm
Attribute	f/2.8 USM	f/2.8 II USM	f/2.8 IS USM	f/2.8 IS II USM	f/2.8 IS III USM	f/4 DO IS USM	f/5.6 USM	f/4 DO IS II USM
Key features
Full-frame compatible	Yes
Image stabilizer	No		Yes				No	Yes
Ultrasonic Motor	Yes
L-series	Yes
Diffractive Optics	No					Yes	No	Yes
Technical data
Aperture (max-min)	f/2.8-f/32					f/4-f/32	f/5.6-f/32	f/4-f/32
Construction	9 groups / 11 elements		13 groups / 17 elements				6 groups / 7 elements	12 groups /18 elements
Aperture blades	8			9		8		9
Closest focusing distance	4m		3m	2.7m	2.5m	3.5m		3.3m
Max. magnification	0.11x		0.15x	0.17x		0.12x	0.11x	0.13x
Diagonal viewing angle	6 °
Physical data
Weight	13.44 lb / 6.1 kg	13.03 lb / 5.91 kg	11.83 lb / 5.37 kg	8.48 lb / 3.85 kg	6.26 lb / 2.84 kg	4.27 lb / 1.94 kg	2.8 lb / 1.25 kg	2.1 kg
Maximum diameter	6.57" / 167mm		6.41" / 163mm			5.03" / 128mm	3.54" / 90mm/	5.04" /128mm
Length	13.70" / 348mm		13.74" / 349mm	13.50" / 343mm		9.16" / 232.7mm	10.09" / 256.5mm	9.16" / 232.7mm
Filter diameter	48mm		52mm drop-in filter				77mm	52mm drop-in
Accessories
Lens hood	ET-161B II		ET-155	ET-155 (WII)	ET-155 (WIII)	ET-120	Built-in	ET120 (WII)
Case			400	400C	400E	400B		400D
Retail information
Release date	April 1991	March 1996	Sept. 1999	Aug. 2011	Sept. 2018	Dec. 2001	May 1993	Sept. 2014

EF 400mm f/4 DO IS USM reviews and articles

• Canon UK / US Information Page
• Amazon
• Northlight Images
• Canon CPN article
• Fred Miranda
• Lens Tip
• Digital Picture
• PhotoZone
• SLR Gear
• Lens Review
• ePhotozine
• Blog - Grant Atkinson

Written a review? Contact us and we'll add it to the list.

Sample images

None available.

Product launch

LAKE SUCCESS, N.Y. Sept. 6, 2000

Canon U.S.A., the company whose imaging solutions give people Know How, today announced the development of the world's first "Multi-Layer Diffractive Optical Element'' for camera lenses.

A prototype Canon EF 400mm f/4 DO IS USM lens incorporating this element will be exhibited at Photokina 2000 in Cologne, Germany, from Sept. 20-25. A commercial version of this lens will be marketed during the first half of 2001.

Canon's history of advanced optical element development includes the creation of fluorite and aspherical elements, which have contributed to the realization of high-performance camera lenses. These optical elements are now found in a diverse range of lens products, such as interchangeable SLR camera lenses, and lenses for video camcorders and digital cameras. Canon's Multi-Layer Diffractive Optical Element, a major innovation in the world of optical technology, represents a milestone in that it possesses the characteristics of both fluorite and aspherical elements.

Diffractive optical elements have a diffraction grating that alters the path light travels through diffraction.(a) Such elements are already incorporated in such industrial instruments as spectroscopes and in signal-reading optical systems found in CD and DVD players. Diffractive optical elements, however, have not been employed in camera lenses due to the tendency of natural (white) light to produce superfluous diffracted light upon entering the lens, resulting in flare that degrades image quality.

Canon's Multi-Layer Diffractive Optical Element features a multi-layer construction comprising two single-layer diffractive optical elements with opposing concentric circular diffraction gratings. When incident light enters the Multi-Layer Diffractive Optical Element, superfluous diffracted light is not produced and almost all of the light is used for the image. The achievement makes possible for the first time the incorporation of a diffractive optical element in a camera lens.

The most significant characteristic of the diffractive optical element is that the positions where the wavelengths combine to form an image are reversed from those of a refractive optical element. By combining a Multi-Layer Diffractive Optical Element and a refractive optical element within the same optical system, chromatic aberration (color smearing), which adversely affects image quality, can be corrected even more effectively than with a fluorite element. Also, by adjusting the pitch (spacing) of the diffraction grating, the diffractive optical element makes possible the same optical characteristics as a ground and polished aspherical surface, which effectively corrects for spherical and other aberrations.

During the manufacture of the Multi-Layer Diffractive Optical Element's diffraction grating, the height and pitch of the diffraction grating as well as its positioning requires micron-level precision (1 micron equals 1/1000 mm). Such exacting accuracy was made possible through Canon's proprietary three-dimensional ultra-high-precision micro manufacturing technologies and the replicated aspherical lens manufacturing technology used in the production of Canon EF lenses. Such advanced technology also makes possible the manufacture of the ultra-precision diffractive optical element.

Canon will continue its research and development efforts with the aim of incorporating the Multi-Layer Diffractive Optical Element in a variety of products, such as interchangeable SLR camera lenses, digital camera lenses, HMDs (Head-Mounted Displays),(b) LCD projector lenses, and other imaging equipment.