Comparison of Canon EF 16-35mm f/2.8L USM and Tokina 12-28mm f/4 AT-X 128 AF PRO DX

Attribute	Canon EF 16-35mm f/2.8L USM ×	Tokina 12-28mm f/4 AT-X 128 AF PRO DX ×
Filter Size (mm)	77	77
Notes	Includes Hood EW-83E, Lens Case LP 1319	Available AF Mounts: Canon and Nikon Digital Only. Built-in AF motor for use with all Nikon DSLRs. Included Accessories: Lens Hood
Closest Focus (m)	0.28	0.25
Magnification Ratio (x)	0.22	0.2
Type	Wide Zoom	Wide Zoom
Length (mm)	103	90.2
APS Equivalent	26 - 56mm	1.5x: 18 - 42mm;1.6x: 19.2 - 44.8mm
Zoom System	Rotary	Rotary
Image Circle	35mm	APS-C
Focal Length (mm)	16.00 - 35.00	12.00 - 28.00
Brand	Canon	Tokina
Name	Canon EF 16-35mm f/2.8L USM	Tokina 12-28mm f/4 AT-X 128 AF PRO DX
Weight (g)	600	530
Aperture (f)	2.80 - 22.00	4.00 - 22.00
Diaphragm Blades	7	9
Diagonal Angle of View (degree)	63.00 - 108.20	54.70 - 99.40
Lens Construction	13 elements in 10 groups, including 3 aspherical and 2 UD elements	14 elements in 12 groups, including 2 aspherical and 2 SD elements
Diameter (mm)	83.5	84
Focus Details	Inner focusing; full-time manual focus and USM;	Internal with One-Touch Focus Clutch mechanism; SD-M (Silent Drive-Module)