Comparison of Sigma 28-200mm f/3.5-5.6 Aspherical IF Macro and Tamron AF 18-200mm f/3.5-6.3 XR Di II LD Aspherical IF

Attribute	Tamron AF 18-200mm f/3.5-6.3 XR Di II LD Aspherical IF ×	Sigma 28-200mm f/3.5-5.6 Aspherical IF Macro ×
Aperture (f)	3.50 - 22.00	3.50 - 22.00
Filter Size (mm)	62	62
Notes	Available mounts: Canon, Minolta, Nikon, Pentax. Includes petal type hood.	Available AF Mounts: Sigma, Canon, Nikon, Minolta, Pentax; Include Accessories: Lens Hood
Closest Focus (m)	0.45	0.48
Magnification Ratio (x)	0.27	0.26
Diameter (mm)	73.8	70
Type	Standard Zoom	Standard Zoom
APS Equivalent	1.5x: 27 - 300mm; 1.6x: 28.8 - 320mm	1.5x: 42 - 300mm; 1.6x: 44.8 - 320mm
Diaphragm Blades	7	8
Image Circle	Image Circle	35mm
Focal Length (mm)	18.00 - 200.00	28.00 - 200.00
Brand	Tamron	Sigma
Name	Tamron AF 18-200mm f/3.5-6.3 XR Di II LD Aspherical IF	Sigma 28-200mm f/3.5-5.6 Aspherical IF Macro
Weight (g)	398	380
Diagonal Angle of View (degree)	7.00 - 75.00	12.30 - 75.40
Lens Construction	15 elements in 13 groups, with low dispersion, aspherical and extra reffractive index elements	16 elements in 14 groups, including 2 aspherical elements
Zoom System	Rotating, Telescoping	Rotary with lock
Length (mm)	83.7	77.7
Front Element Rotation	-	-
Focus Details	Internal focusing system	Internal