Comparison of Canon EF 15mm f/2.8 Fisheye and Sigma 8mm f/4 EX DG Circular Fisheye

Attribute	Canon EF 15mm f/2.8 Fisheye ×	Sigma 8mm f/4 EX DG Circular Fisheye ×
Brand	Canon	Sigma
Name	Canon EF 15mm f/2.8 Fisheye	Sigma 8mm f/4 EX DG Circular Fisheye
Focal Length (mm)	15.00	8.00
Image Circle	35mm	35mm
Diaphragm Blades	5	5
APS Equivalent	24mm	1.5x: 12mm; 1.6x: 12.8mm
Focus Details	Focus Details	-
Length (mm)	73	63
Magnification Ratio (x)	0.14	0.07
Closest Focus (m)	0.2	0.2
Notes	Fixed, petal-type hood; rear gelatin filter holder	Available AF Mounts: Sigma, Canon, Nikon, Minolta, Pentax; Included Accessories: Gelatin Filter Holder, Fitted, Padded Case
Aperture (f)	2.80 - 22.00	4.00 - 32.00
Diagonal Angle of View (degree)	180.00	180.00
Weight (g)	330	320
Lens Construction	8 elements in 7 groups	10 Elements in 6 Groups
Type	Fisheye Prime	Fisheye Prime
Diameter (mm)	62	73.5