Comparison of Olympus 8mm ƒ/1.8 Pro M.Zuiko Digital ED Fisheye and Sigma 15mm f/2.8 EX DG Diagonal Fisheye

Attribute	Sigma 15mm f/2.8 EX DG Diagonal Fisheye ×	Olympus 8mm ƒ/1.8 Pro M.Zuiko Digital ED Fisheye ×
Weight (g)	370	313
Brand	Sigma	Olympus
Name	Sigma 15mm f/2.8 EX DG Diagonal Fisheye	Olympus 8mm ƒ/1.8 Pro M.Zuiko Digital ED Fisheye
Focal Length (mm)	15.00	8.00
Image Circle	35mm	Image Circle
Length (mm)	65	80
Diaphragm Blades	7	7
Magnification Ratio (x)	0.26	0.2
Closest Focus (m)	0.15	0.12
Aperture (f)	2.80 - 22.00	1.80 - 22.00
Notes	Available AF Mounts: Sigma, Canon, Nikon, Minolta, Pentax	Weather sealed; Fixed lens hood and a pinch-style lens cap LC-62 included.
Diaphragm Blades Type	-	circular
Diagonal Angle of View (degree)	180.00	180.00
Diameter (mm)	73.5	62
Type	Fisheye Prime	Fisheye Prime
Lens Construction	7 elements in 6 groups	17 elements in 15 groups, including 1 aspherical, 3 Super ED, 2 ED, 1 Super HR, and 2 HR elements
APS Equivalent	1.5x: 22.5mm; 1.6x: 24mm	-
35mm Equivalent	-	16mm