Like every autofocus Canon "L" lens, the EF 70-200mm f/4LUSM delivers optical performance equal to similar fixed focal length lenses, with silent, high-speed ultrasonic (USM) focusing and full-time manual focus override capacity. A focus range limiting option also enables faster autofocus rates.
Distortions and aberrations are remarkably small for a lens of such capability. This lens combines 1 artificial fluorite element with 2 UD (Ultra-low Dispersion) elements to help achieve images free of secondary spectrum aberrations, which are often the bane of consumer-grade telephoto zooms. It is li