The RF mount design inherits the superior optics of the EF400mm f/2.8L IS III USM, offering high image quality and light weight. Two fluorite lenses and a super Ultra-low Dispersion (UD) lens provide high-resolution, high-contrast imaging performance. This is Canons flagship super-telephoto lens for professionals and advanced amateurs, offering clear, sharp, high image quality with no color bleeding. The light weight enhances mobility and allows photographers to capture stunning high-quality images. This lens is equipped with a switch that allows the user to select from three manual focus speeds. It also features a thermal barrier coating to prevent the lens body from accumulating heat, when used in the hot sun. The image stabilization effect of the lens alone is 5.5 stops*.
* According to CIPA standards.
| Angle of View (Horizontal/Vertical/Diagonal) | 05°10’ / 03°30’ / 06°10’ |
| Lens Construction | 17 elements in 13 groups |
| Aperture Blades | 9 |
| Min. Aperture | 32 |
| Min. Focusing Distance | 2.5m |
| Max. Magnification | 0.17x |
| Filter Size | 52mm (Drop-in filter) |
| Max. Diameter x Length | Approx. φ163mm x 367mm |
| Weight | Approx. 2,890g |
