Samyang 8mm f/3.5 Fisheye CS II

The Samyang 8mm F3.5 UMC Fish-Eye CS II is a fisheye photographic lens using the stereographic projection[1] and is designed for crop factor APS-C DSLRs.[2] It is made in South Korea by Samyang Optics and marketed under several brand names besides Samyang, including Bower, Falcon, Polar, Pro-Optic, Rokinon, Vivitar and Walimex Pro (Walser GmbH & Co. KG). There are versions for the Canon EF, Fujifilm X, Nikon F, MFT, Pentax K, Samsung NX, Sony E, Sony α/Minolta A mounts.

Samyang 8mm F3.5 UMC Fish-Eye CS II

Rokinon brand, older version without removable lens hood
Maker	Samyang Optics
Lens mount(s)	Canon EF, Fuji X, Nikon F, MFT, Pentax K, Samsung NX, Sony E, Sony α/Minolta A
Technical data
Type	fisheye
Focal length	8 mm
Focal length (35mm equiv.)	12 mm (except Canon, 12.8 mm, and MFT, 16 mm)
Aperture (max/min)	f/3.5–f/22
Close focus distance	0.3 m (0.98 ft)
Max. focus distance	∞
Diaphragm blades	7
Construction	10 elements in 7 groups
Features
Lens-based stabilization	No
Macro capable	No
Aperture ring	Yes
Unique features	Diagonal fisheye
Application	video, general
Physical
Max. length	72.6–101.4 mm (2.86–3.99 in) depending on mount
Diameter	77.8 mm (3.06 in)
Weight	410–515 g (14.5–18.2 oz) depending on mount
Filter diameter	N not possible
Accessories
Lens hood	Y yes, fixed except Nikon
Angle of view
Diagonal	139.3°–180° depending on mount

The lens uses manual focus only. For most versions of the lens, the aperture must be set manually. For Nikon there are versions with and without a chip to communicate aperture information with the camera. Versions with the chip (model AE8M-N) can set the aperture automatically. The CS II version of the lens has a removable lens hood.