Overview

The Canon EF 600mm f/4L IS USM is a heavy (11.8 lbs), large super-telephoto lens built with a magnesium alloy barrel and weather sealing, offering excellent build quality. Optically, it delivers decent sharpness wide open, improving when stopped down, with slight vignetting at f/4. The image stabilizer allows handheld use at slower shutter speeds. Autofocus is fast and quiet via USM. It suits bird, wildlife, and distant sports photographers who need extreme reach and can manage its size, weight, and cost.