Comparison of Pentax SMC P-FA 600mm f/4 ED IF and Sigma 200-500mm f/2.8 EX DG APO

Attribute	Sigma 200-500mm f/2.8 EX DG APO ×	Pentax SMC P-FA 600mm f/4 ED IF ×
Aperture (f)	2.80 - 22.00	4.00 - 32.00
Diagonal Angle of View (degree)	-	4.10
Filter Size (mm)	72	43
Notes	Available AF Mounts: Sigma, Canon, Nikon; The dedicated 2x "Attachment" ensures autofocusing at the 1000mm focal length.	Included Accessories: Case
Type	Telephoto Zoom	Telephoto Prime
Closest Focus (m)	2	5
APS Equivalent	1.5x: 300 - 750mm; 1.6x: 320 - 800mm	900mm
Magnification Ratio (x)	0.13	-
Image Circle	35mm	35mm
Focal Length (mm)	200.00 - 500.00	600.00
Brand	Sigma	Pentax
Name	Sigma 200-500mm f/2.8 EX DG APO	Pentax SMC P-FA 600mm f/4 ED IF
Weight (g)	15700	6450
Diameter (mm)	236.5	175
Lens Construction	17 elements in 13 groups, including SLD and 3 ELD elements	9 elements in 7 groups
Diaphragm Blades	9	-
Length (mm)	726	457
Zoom System	Power Zoom	-
Focus Details	Internal	Internal