Compact, fast and extremely sharp all the way from f/2.8 from close-up to long distances. This lens is also virtually distortion free and ideally suited for technical work. Fast USM AF makes it suitable also for portraits and general photography. ALso, the lens does not get longer when focusing. Additinally, the distance scale and enlargement scale are clear and detailed. A very solid short telephoto all-purpose lens that focuses down to 1:1, great for all suitable cameras.
Visible vignetting at f/2.8, virtually disappears at f/5.6. DIffraction makes the smallest f-stops less usable.