Comparison of Canon EF 20-35mm f/3.5-4.5 USM and Vivitar 19-35mm f/3.5-4.5 Series 1 AF

Attribute	Canon EF 20-35mm f/3.5-4.5 USM ×	Vivitar 19-35mm f/3.5-4.5 Series 1 AF ×
Magnification Ratio (x)	0.13	0.08
Filter Size (mm)	77	77
Focus Details	Inner focusing; full-time manual focus and USM;	-
Closest Focus (m)	0.34	0.5
Lens Construction	12 elements in 11 groups	13 elements in 11 groups
Length (mm)	68.9	69
Focal Length (mm)	20.00 - 35.00	19.00 - 35.00
Zoom System	Rotary	Rotary
Brand	Canon	Vivitar
Image Circle	35mm	35mm
Name	Canon EF 20-35mm f/3.5-4.5 USM	Vivitar 19-35mm f/3.5-4.5 Series 1 AF
Weight (g)	340	300
Type	Wide Zoom	Wide Zoom
Aperture (f)	3.50 - 27.00	3.50 - 27.00
APS Equivalent	32 - 56mm	1.5x: 28.5 - 52.5mm; 1.6x: 30.4 - 56mm
Diagonal Angle of View (degree)	63.00 - 94.00	63.00 - 97.00
Diaphragm Blades	5	-
Notes	-	Available AF mounts: Canon, Minolta, Nikon, Pentax
Diameter (mm)	83.5	82