EF50mm f/1.0L USM
| Marketed |
September 1989 |
| Lens Construction (group) |
9 |
| Lens Construction (element) |
11 |
| No. of Diaphragm Blades |
8 |
| Minimum Aperture |
16 |
| Closest Focusing Distance (m) |
0.95 |
| Maximum Magnification (x) |
0.11 |
| Filter Diameter (mm) |
72 |
| Maximum Diameter x Length (mm) |
91.5 x 81.5 |
| Weight (g) |
985 |
An ultra-fast standard lens with the largest aperture for SLR lenses in the world at the time. Two large-diameter ground and polished glass aspherical lens elements (3rd & 8th) provide high-contrast with low-flare image quality even at maximum aperture. Curvature of field is minimized through use of four high-refraction glass elements. Spherical aberration and curvature of field at close focusing distance are minimized by floating mechanism. A ring USM (Ultrasonic Motor) achieves silent, high-speed AF and full-time manual focusing.
