Comparison of Olympus 100-400mm f/5.0-6.3 IS ED M.Zuiko Digital and Sigma 120-300mm f/2.8 EX DG OS HSM APO

Attribute	Sigma 120-300mm f/2.8 EX DG OS HSM APO ×	Olympus 100-400mm f/5.0-6.3 IS ED M.Zuiko Digital ×
Aperture (f)	2.80 - 22.00	5.00 - 22.00
Diaphragm Blades Type	rounded	rounded
Filter Size (mm)	105	72
Notes	Image Stabilized (up to 4 stops). Available AF Mounts: Sigma, Canon, Nikon. Included Accessories: Bayonet type Hood (LH1128-01), Tripod socket (TS-31	Built-in image stabilization CIPA rated for 3.0 stops, Not supported with 5-axis Sync IS; IPX1-rated Dust and splash-proof weather sealing
APS Equivalent	1.5x: 180 - 450mm; 1.6x: 192 - 480mm	-
Type	Telephoto Zoom	Telephoto Zoom
Diaphragm Blades	9	9
Diameter (mm)	114.4	86.5
Image Circle	35mm	Image Circle
Focal Length (mm)	120.00 - 300.00	100.00 - 400.00
Brand	Sigma	Olympus
Name	Sigma 120-300mm f/2.8 EX DG OS HSM APO	Olympus 100-400mm f/5.0-6.3 IS ED M.Zuiko Digital
Weight (g)	-	1.12
Diagonal Angle of View (degree)	8.20 - 20.40	12.00
Lens Construction	23 elements in 18 groups, including 1 SLD and 2 FLD elements	21 elements in 15 groups (4 ED lenses, 2 Super HR lenses, 2 HR lenses); ZERO coating
Zoom System	Rotary; Internal	Rotary
Closest Focus (m)	1.5	1.3
35mm Equivalent	-	200-800mm
Length (mm)	289.2	205.7
Focus Details	Internal; HSM with full-time manual override	-
Magnification Ratio (x)	0.12	0.09