|Lens type||Prime lens|
|Max Format size||35mm FF|
|Focal length||400 mm|
|CIPA Image stabilization rating||5.5 stop(s)|
|Lens mount||Canon RF|
|Number of diaphragm blades||9|
|Special elements / coatings||1 Super UD + 2 fluorite elements, Super Spectra + ASC coatings|
|Minimum focus||2.50 m (98.43″)|
|Motor type||Ring-type ultrasonic|
|Full time manual||Yes|
|Focus distance limiter||Yes|
|Weight||2890 g (6.37 lb)|
|Diameter||168 mm (6.61″)|
|Length||367 mm (14.45″)|
|Filter thread||52 mm|
|Filter notes||Rear drop-in filters only|
The Canon RF 400mm F2.8L IS USM is a super-telephoto prime for the company’s full-frame mirrorless system. The lens, which uses the same optical formula as the EF version, features 17 elements in 13 groups, with one super UD and two fluorite elements. Super Spectra and Air Sphere coatings reduce ghosting and flare. The image stabilizer reduces shake by up to 5.5 stops.
The lens has a minimum focus distance of 2.5m (8.2 ft) and a magnification of 0.17x. Three focus limit modes are available: full, 2.5-7.5m and 7.5 to infinity. The 400mm F2.8 supports 52mm drop-in filters and Canon’s 1.4x and 2x teleconverters.
As with all L-series lenses, the 400mm F2.8 is sealed against dust and moisture, and the fluorine coating on the front element repels oil and water.