Comparison of M.Zuiko Digital ED 12-45mm F4.0 PRO and Sigma 18-50mm f/3.5-5.6 DC

Attribute	M.Zuiko Digital ED 12-45mm F4.0 PRO ×	Sigma 18-50mm f/3.5-5.6 DC ×
Diaphragm Blades Type	rounded	-
Notes	Dustproof and splashproof construction (IPX1 rating)	Available AF Mounts: Canon, Nikon, Minolta/Sony, Pentax, Four-Thirds, Sigma; HSM version available for Nikon mount
Aperture (f)	4.00 - 22.00	3.50 - 22.00
Type	Standard Zoom	Standard Zoom
Filter Size (mm)	58	58
Diameter (mm)	63.4	62
APS Equivalent	-	1.5x: 27 - 75mm; 1.6x: 28.8 - 80mm
Diaphragm Blades	7	7
Lens Construction	12 elements in 9 groups, including 2 HR lenses, 1 DSA lens, 1 Super HR lens, 2 Aspherical lenses, 2 ED elements	8 elements in 8 groups
Image Circle	Micro Four-Thirds	Image Circle
Focal Length (mm)	12.00 - 45.00	18.00 - 50.00
Brand	Olympus	Sigma
Name	M.Zuiko Digital ED 12-45mm F4.0 PRO	Sigma 18-50mm f/3.5-5.6 DC
Weight (g)	254	250
Diagonal Angle of View (degree)	27.00 - 84.00	27.90 - 69.30
Focus Details	High-speed Imager AF (MSC)	Internal; HSM version available for Nikon mount
Zoom System	Rotary	Rotary
Length (mm)	70	67.5
35mm Equivalent	24 - 90mm	-
Magnification Ratio (x)	0.25	0.29
Front Element Rotation	-	-
Closest Focus (m)	0.12	0.25