When used with a 77mm diameter wide-angle zoom lens, the lens corrects image aberration and distortion*. The lens helps reproduce clear images when mounted on a compatible lens for interchangeable lens cameras (full-frame SLR cameras).
* Field curvature and distortion are reduced by approximately 2 f-stops value.
Compatible Lenses: Canon EF17-40mm F4L USM, Canon EF 16-35mm F4L IS USM, Nikon AF-S 16-35mm F4G ED VR, Nikon AF-S Nikkor 18-35mm F3.5-4.5G ED
Lens: 1 element in 1 group (AR-multi-coated on both sides)
Dimensions (WxHxD) 85 x 8.4mm / 3.3 x 0.3 inches
Weight: 48g / 1.7oz
Construction: Optical glass (AR-multi-coated on the both sides) and corrosion-resistant aluminum alloy.