Comparison of Nikon 55mm ƒ/2.8 AIS Micro-Nikkor and Sigma Macro 50mm f/2.8 EX DG

Attribute	Sigma Macro 50mm f/2.8 EX DG ×	Nikon 55mm ƒ/2.8 AIS Micro-Nikkor ×
Closest Focus (m)	0.19	0.25
Magnification Ratio (x)	1	0.5
Focus Details	-	Manual Focus Only; Close Range Correction
Front Element Rotation	-	-
Lens Construction	10 elements in 9 groups	6 elements in 5 groups
Length (mm)	66.5	60.9
Focal Length (mm)	50.00	55.00
Aperture (f)	2.80 - 45.00	2.80 - 32.00
Brand	Sigma	Nikon
Image Circle	35mm	35mm (FX)
Name	Sigma Macro 50mm f/2.8 EX DG	Nikon 55mm ƒ/2.8 AIS Micro-Nikkor
Weight (g)	320	286
Type	Standard Prime Macro	Standard Macro Prime
Filter Size (mm)	55	52
APS Equivalent	1.5x: 75mm; 1.6x: 80mm	82.5mm
Notes	Available AF Mounts: Sigma, Canon, Nikon, Minolta, Pentax; Included Accessories: Lens Hood	Classic Nikon F Mount; AIS / AI / NAI Metering Compatibility; Includes front and rear lens caps.
Diaphragm Blades	7	7
Diagonal Angle of View (degree)	46.80	43.00
Diameter (mm)	71.4	63.5