The ultra-wide Zeiss Distagon T* 18mm f/3.5 ZF.2 Lens for Nikon F-mount Cameras is a precision manual focus prime lens that provides excellent image performance over its entire image range from 0.98' (0.3 m) to infinity. Combined with the legendary Zeiss T* anti-reflective coating, the Distagon T* 18mm f/3.5 delivers brilliant pictures even under difficult lighting conditions. This professional lens, when mounted to a digital SLR using a DX-type sensor, has an effective focal length of 27mm (35mm equivalent).