Comparison of Canon EF 200-400mm f/4L IS USM Extender 1.4X and Sigma APO 300-800 f/5.6 EX DG HSM

Attribute	Sigma APO 300-800 f/5.6 EX DG HSM ×	Canon EF 200-400mm f/4L IS USM Extender 1.4X ×
Notes	Available AF Mounts: Sigma, Canon, Nikon, Four-Thirds	Built-in 1.4x extender (8 elements in 4 groups) switches to 280-560mm f/5.6 lens with 0.21x / 1.48 magnification ratio; 4-stop Image Stabilization
Magnification Ratio (x)	0.14	0.15
Filter Size (mm)	46	52
Length (mm)	544	366
Closest Focus (m)	6	2
Diagonal Angle of View (degree)	3.10 - 8.20	6.20 - 12.00
Focus Details	Internal; HSM with full-time manual override	Inner focusing; Full-time manual focus and ring USM; Ring USM, High-speed CPU and optimized AF algorithms; Power Focus mode; Focus Limiter
Focal Length (mm)	300.00 - 800.00	200.00 - 400.00
APS Equivalent	1.5x: 450 - 1200mm; 1.6x: 480 - 1280mm	320 - 640mm
Brand	Sigma	Canon
Image Circle	35mm	35mm
Name	Sigma APO 300-800 f/5.6 EX DG HSM	Canon EF 200-400mm f/4L IS USM Extender 1.4X
Weight (g)	5880	3620
Type	Telephoto Zoom	Telephoto Zoom
Aperture (f)	5.60 - 32.00	4.00 - 32.00
Diaphragm Blades	9	9
Diaphragm Blades Type	-	circular
Lens Construction	18 elements in 16 groups, including 2 ELD elements	25 elements in 20 groups (incl. 1 rear filter); one fluorite and four UD lens elements
Zoom System	Rotary	Rotating
Diameter (mm)	165.5	128