Samyang 8mm F2.8 UMC Fisheye II (Black) Lens for Samsung NX Mount Digital Cameras (SY8MBK28-NX) Fixed 8mm focal Length; Fisheye lens Aperture range of f2.8-22 New and improved optics and construction Constructed of 11 elements in 8 groups; built specifically for mirror less cameras Minimum focusing distance of 1 foot.