Comparison of Olympus 9-18mm f/4-5.6 ED Zuiko Digital and Tamron SP AF 11-18mm f/4.5-5.6 Di II LD Aspherical IF

Attribute	Tamron SP AF 11-18mm f/4.5-5.6 Di II LD Aspherical IF ×	Olympus 9-18mm f/4-5.6 ED Zuiko Digital ×
Zoom System	Rotary, telescoping	Rotary
Aperture (f)	4.50 - 29.00	4.00 - 22.00
Diagonal Angle of View (degree)	75.00 - 103.00	62.00 - 100.00
Filter Size (mm)	77	72
Notes	Available mounts: Canon, Minolta, Nikon; Includes petal type lens hood.	Includes lens cap, lens hood
Focus Details	Internal	-
Type	Wide Zoom	Wide Zoom
Diaphragm Blades	7	7
Lens Construction	15 elements in 12 groups, including aspherical and low dispersion elements	13 elements in 9 groups, including 1 aspherical ED lens and 2 aspherical elements
Image Circle	Image Circle	Image Circle
Focal Length (mm)	11.00 - 18.00	9.00 - 18.00
Brand	Tamron	Olympus
Name	Tamron SP AF 11-18mm f/4.5-5.6 Di II LD Aspherical IF	Olympus 9-18mm f/4-5.6 ED Zuiko Digital
Weight (g)	355	280
Diameter (mm)	82.2	79.5
Length (mm)	78.6	73
35mm Equivalent	-	18 - 36mm
Magnification Ratio (x)	0.13	0.24
APS Equivalent	1.5x: 16.5 - 27mm; 1.6x: 17.6 - 28.8mm	-
Closest Focus (m)	0.25	0.25