Comparison of Tamron SP AF 17-50mm ƒ/2.8 XR Di II VC LD Aspherical IF and Tokina 16-50mm f/2.8 AT-X 165 AF PRO DX

Attribute	Tokina 16-50mm f/2.8 AT-X 165 AF PRO DX ×	Tamron SP AF 17-50mm ƒ/2.8 XR Di II VC LD Aspherical IF ×
Notes	Available AF Mounts: Canon, Nikon; Included Accessories: Lens Hood	Vibration Compensation (VC) Image Stabilization; Available AF mounts: Canon, Nikon; Includes petal type lens hood.
Magnification Ratio (x)	0.2	0.21
Filter Size (mm)	77	72
Length (mm)	97.4	94.5
Closest Focus (m)	0.3	0.29
Diagonal Angle of View (degree)	31.00 - 82.00	31.20 - 78.80
Focus Details	Internal with One-Touch Focus Clutch mechanism	Internal, with built-in focus motor
Focal Length (mm)	16.00 - 50.00	17.00 - 50.00
APS Equivalent	1.5x: 24 - 75mm; 1.6x: 25.6 - 80mm	1.5x: 25.5 - 75mm; 1.6x: 27.2 - 80mm
Brand	Tokina	Tamron
Image Circle	APS-C	Image Circle
Name	Tokina 16-50mm f/2.8 AT-X 165 AF PRO DX	Tamron SP AF 17-50mm ƒ/2.8 XR Di II VC LD Aspherical IF
Weight (g)	610	570
Type	Standard Zoom	Standard Zoom
Aperture (f)	2.80 - 22.00	2.80 - 32.00
Diaphragm Blades	9	7
Diaphragm Blades Type	-	rounded
Lens Construction	15 elements in 12 groups, including 1 SD element	19 elements in 14 groups, including Low Dispersion and Aspherical elements
Zoom System	Rotary	Rotary
Diameter (mm)	84	79.6