This helps to reduce ghosting and flare, but its main benefit is that it protects the lens’s bulbous front element.
Ring-type ultrasonic or ‘hypersonic’ AF is fairly rapid and whisper-quiet. It also has a full-time manual override facility in ‘single’ autofocus mode.
The metal mounting plate includes a built-in holder for the insertion of gel filters.
Elements/groups: 12/7 Aperture range: f/2.8 to f/22 Autofocus type: Ring-type ultrasonic Minimum focus distance: 0.13m Maximum magnification: 0.3x Filter thread: Rear filter holder Dimensions: 76x83mm Weight: 475g