Comparison of Sigma 10-20mm ƒ/3.5 EX DC HSM and Tokina 11-20mm f/2.8 AT-X PRO DX SD

Attribute	Tokina 11-20mm f/2.8 AT-X PRO DX SD ×	Sigma 10-20mm ƒ/3.5 EX DC HSM ×
Filter Size (mm)	82	82
Notes	Available AF Mounts: Canon EF, Nikon F (lens has focus motor); Included Accessories: BH-821 Lens Hood	Available AF mounts: Sigma, Canon, Nikon, Sony, Pentax; Included Accessories: Soft Case, Petal-type Hood
Closest Focus (m)	0.28	0.24
Magnification Ratio (x)	0.12	0.15
Type	Wide Zoom	Wide Zoom
Length (mm)	92	88.2
APS Equivalent	1.5x: 16.5 - 30mm; 1.6x: 17.6 - 32mm	1.5x: 15 - 30mm; 1.6x: 16 - 32mm
Zoom System	Rotary	Rotary
Image Circle	APS-C	Image Circle
Focal Length (mm)	11.00 - 20.00	10.00 - 20.00
Brand	Tokina	Sigma
Name	Tokina 11-20mm f/2.8 AT-X PRO DX SD	Sigma 10-20mm ƒ/3.5 EX DC HSM
Weight (g)	560	520
Aperture (f)	2.80 - 22.00	3.50 - 22.00
Diaphragm Blades	9	7
Diagonal Angle of View (degree)	72.70 - 104.50	63.80 - 102.40
Lens Construction	14 elements in 12 groups, including 2 SD (Super-low Dispersion) and 3 aspheric elements	13 elements in 10 groups, including 4 aspherical, 1 SLD and 2 ELD elements
Diameter (mm)	89	87.3
Focus Details	Internal with One-Touch Focus Clutch mechanism	Internal with HSM