Comparison of Canon EF 500mm ƒ/4L IS II USM and Sigma APO 500mm f/4.5 EX DG HSM

Attribute	Canon EF 500mm ƒ/4L IS II USM ×	Sigma APO 500mm f/4.5 EX DG HSM ×
Aperture (f)	4.00 - 32.00	4.50 - 32.00
Filter Size (mm)	52	46
Notes	Image Stabilization (up to 4-stops), includes new Mode 3 that activates IS only when the shutter button is fully pressed.	Available AF Mounts: [HSM version]: Sigma, Canon, Nikon; [w/o HSM]: Minolta, Pentax
Closest Focus (m)	3.7	4
Magnification Ratio (x)	0.15	0.13
Type	Telephoto Prime	Telephoto Prime
Focus Details	Inner focusing; full-time manual focus and USM	Internal; HSM with full-time manual override
APS Equivalent	800mm	1.5x: 750mm; 1.6x: 800mm
Diaphragm Blades	9	9
Image Circle	35mm	35mm
Focal Length (mm)	500.00	500.00
Brand	Canon	Sigma
Name	Canon EF 500mm ƒ/4L IS II USM	Sigma APO 500mm f/4.5 EX DG HSM
Weight (g)	3190	3150
Diagonal Angle of View (degree)	5.00	5.00
Length (mm)	383	350
Diameter (mm)	146	123
Lens Construction	16 elements in 12 groups; Fluorite: G2 and G4, UD Lens: None	12 elements in 9 groups, including 2 ELD elements