Comparison of Canon EF 75-300mm f/4-5.6 III and Canon EF 100-300mm f/4.5-5.6 USM

Attribute	Canon EF 100-300mm f/4.5-5.6 USM ×	Canon EF 75-300mm f/4-5.6 III ×
Closest Focus (m)	1.5	1.5
Magnification Ratio (x)	0.2	0.25
Focus Details	Inner focusing; full-time manual focus and USM	Front group rotating extension system with Micromotor
Front Element Rotation	-	-
Lens Construction	13 elements in 10 groups	13 elements in 9 groups
Length (mm)	121	122
Focal Length (mm)	100.00 - 300.00	75.00 - 300.00
Diagonal Angle of View (degree)	8.30 - 24.00	8.30 - 32.20
Brand	Canon	Canon
Image Circle	35mm	35mm
Name	Canon EF 100-300mm f/4.5-5.6 USM	Canon EF 75-300mm f/4-5.6 III
Weight (g)	540	480
Type	Telephoto Zoom	Telephoto Zoom
Filter Size (mm)	58	58
APS Equivalent	160 - 480mm	120 - 480mm
Aperture (f)	4.50 - 38.00	4.00 - 45.00
Diaphragm Blades	8	7
Zoom System	Rotary	Rotary
Diameter (mm)	73	71