Specifications for the EF 20mm f/2.8 USM Marketed June 1992 Lens Construction (group) 9 Lens Construction (element) 11 No. of Diaphragm Blades 5 Minimum Aperture 22 Closest Focusing Distance (m) 0.25 Maximum Magnification (x) 0.14 Filter Diameter ( mm ) 72 Maximum Diameter x Length ( mm ) 77 .5 x 70.6 Weight (g) 405
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