Comparison of Sigma 18-300mm f/3.5-6.3 DC Macro OS HSM Contemporary and Tamron 18-400mm f/3.5-6.3 Di II VC HLD (Model B028)

Attribute	Tamron 18-400mm f/3.5-6.3 Di II VC HLD (Model B028) ×	Sigma 18-300mm f/3.5-6.3 DC Macro OS HSM Contemporary ×
Aperture (f)	3.50 - 40.00	3.50 - 22.00
Filter Size (mm)	72	72
Notes	Image Stabilization (CIPA 2.5 stops); Available mounts: Canon and Nikon; Includes petal type lens hood; Compatible with TAP-in Console	Image Stabilization; Available OS AF mounts: Canon EF, Nikon F, Sigma SA; Non-OS AF mounts: Sony A, Pentax K
Closest Focus (m)	0.45	0.38
Magnification Ratio (x)	0.34	0.33
Zoom System	Rotary (extending) with zoom lock switch	Rotary
Type	Standard Zoom	Standard Zoom
APS Equivalent	1.5x: 27 - 600mm; 1.6x: 28.8 - 640mm	1.5x: 27 - 450mm; 1.6x: 28.8 - 480mm
Diaphragm Blades	7	7
Image Circle	Image Circle	Image Circle
Focal Length (mm)	18.00 - 400.00	18.00 - 300.00
Brand	Tamron	Sigma
Name	Tamron 18-400mm f/3.5-6.3 Di II VC HLD (Model B028)	Sigma 18-300mm f/3.5-6.3 DC Macro OS HSM Contemporary
Weight (g)	710	585
Diaphragm Blades Type	rounded	rounded
Lens Construction	16 elements in 11 groups, including 3 LD (low dispersion) and 3 aspherical elements	17 elements in 13 groups, including 1 SLD and 4 FLD elements; Super Multi-Layer Coating
Diagonal Angle of View (degree)	4.00 - 75.55	5.40 - 76.50
Length (mm)	123.9	101.5
Diameter (mm)	79	79
Focus Details	Internal with HLD motor	Internal HSM (Hyper Sonic Motor) with AF/MF switch