EF Lenses


EF400mm f/4 DO IS USM

  • Specifications
  • Block diagram
Marketed December 2001
Original Price 770,000 yen (w/case)
Lens Construction (group) 13
Lens Construction (element) 17
No. of Diaphragm Blades 8
Minimum Aperture 32
Closest Focusing Distance (m) 3.5
Maximum Magnification (x) 0.12
Filter Diameter (mm) 52
Maximum Diameter x Length (mm) 128 x 232.7
Weight (g) 1,940

The EF400mm f/4 DO IS USM is the world’s first super telephoto lens incorporating the exclusive Canon-developed multi-layer diffractive optical element for camera lenses. The optical element, which incorporates light diffraction, is a major technological breakthrough, and it features an exceeding ability to correct chromatic and spherical aberrations and render high-quality images. By including this optical element in the lens design, the lens has achieved tremendous savings of 26% in overall length and 36% in weight compared to comparable lenses incorporating only conventional refractive optical elements. Moreover, the size and weight advantage comes at no cost to image quality, with the EF400mm f/4 DO IS USM delivering performance equivalent to conventional models in its class.

Block diagram

DO Lens  Fluorite Lenses