- Diagonal Angle of View: 5°.
- Lens Construction (elements/groups): 17/13.
- Closest Focusing Distance (m): 4.5.
- Focus adjustment: Inner focusing system with USM.
- Filter Diameter (mm): 52 Rear Drop-in.
This 500mm super telephoto lens with Image Stabilizer system and large aperture of f/4 is sure to have wide appeal. Its newly designed optical system consists of 17 elements in 13 groups, including one fluorite lens and two UD lenses. These have eliminated all kinds of aberrations to achieve a level of image quality previously impossible to attain. With ring USM and an improved drive algorithm, its autofocus is the fastest in the world (when used with the EOS-3). The large f/4 aperture permits the use of autofocus when using an extender. The lens's closest focusing distance has been reduced to only 4.5m/ 14.8ft., and it is equipped with full-time mechanical manual focus, a focus preset function, and an AF Stop function. The use of a magnesium alloy for the lens barrel minimizes weight and the lens offers superior dust-proof and moisture-proof performance.