Comparison of Sigma 18-250mm f/3.5-6.3 DC Macro OS HSM and Tamron 28-300mm f/3.5-6.3 XR Di VC LD Aspherical IF Macro AF

Attribute	Tamron 28-300mm f/3.5-6.3 XR Di VC LD Aspherical IF Macro AF ×	Sigma 18-250mm f/3.5-6.3 DC Macro OS HSM ×
Notes	Image Stabilization; Available mounts: Canon and Nikon; Includes petal type lens hood.	Image Stabilization; Available AF mounts: Sigma, Sony, Nikon, Canon and Pentax.
Magnification Ratio (x)	0.33	0.34
Filter Size (mm)	67	62
Length (mm)	99	88.6
Closest Focus (m)	0.49	0.35
Diagonal Angle of View (degree)	8.25 - 75.38	5.70 - 69.30
Focus Details	Internal	Internal HSM (Hyper Sonic Motor) with AF/MF switch
Focal Length (mm)	28.00 - 300.00	18.00 - 250.00
APS Equivalent	1.5x: 42 - 450mm; 1.6x: 44.8 - 480mm	1.5x: 27 - 375mm; 1.6x: 28.8 - 400mm
Brand	Tamron	Sigma
Image Circle	Image Circle	Image Circle
Name	Tamron 28-300mm f/3.5-6.3 XR Di VC LD Aspherical IF Macro AF	Sigma 18-250mm f/3.5-6.3 DC Macro OS HSM
Weight (g)	550	470
Type	Standard Zoom	Standard Zoom
Aperture (f)	3.50 - 40.00	3.50 - 22.00
Diaphragm Blades	9	7
Diaphragm Blades Type	-	rounded
Lens Construction	18 elements in 13 groups; including aspherical, LD (low dispersion) and AD (anomalous dispersion) elements.	16 elements in 13 groups, including 1 Special Low Dispersion (SLD) and 3 aspherical elements
Zoom System	Rotary, telescoping	Rotary
Diameter (mm)	78	73.5