Comparison of Panasonic 16-35mm f/4 Lumix S Pro (S-R1635) and Tamron 17-35mm f/2.8-4 Di OSD (Model A037)

Attribute	Panasonic 16-35mm f/4 Lumix S Pro (S-R1635) ×	Tamron 17-35mm f/2.8-4 Di OSD (Model A037) ×
Filter Size (mm)	77	77
Notes	Splash- and dust-resistant. Included Accessories: front and rear lens caps, lens hood, storage bag.	Available mounts: Canon EF, Nikon F; Moisture-resistant construction; Includes petal type lens hood.
Closest Focus (m)	0.25	0.28
Magnification Ratio (x)	0.23	0.2
Diameter (mm)	85	83.2
Type	Wide Zoom	Wide Zoom
APS Equivalent	24 - 52.5mm	-
Diagonal Angle of View (degree)	63.00 - 107.00	63.40 - 103.70
Image Circle	35mm (L-Mount)	Image Circle
Focal Length (mm)	16.00 - 35.00	17.00 - 35.00
Brand	Panasonic	Tamron
Name	Panasonic 16-35mm f/4 Lumix S Pro (S-R1635)	Tamron 17-35mm f/2.8-4 Di OSD (Model A037)
Weight (g)	500	459
Aperture (f)	4.00 - 22.00	2.80 - 22.00
Diaphragm Blades	9	7
Diaphragm Blades Type	circular	circular
Lens Construction	12 elements in 9 groups, including 1 UHR (Ultra-High Refractive Index), 1 ED and 3 aspherical elements; Fluorine coating on front element.	15 elements in 10 groups, including 4 LD (Low Dispersion) and 2 GM (Glass Molded) aspherical elements BBAR (Broad-Band Anti-Reflection) coating
Zoom System	Rotary	Rotary
Length (mm)	99.6	91.4
35mm Equivalent	-	1.5x: 25.5 - 52.5mm; 1.6x: 27.2 - 56mm
Focus Details	Internal with double-magnet linear motor; AF/MF clutch mechanism	Internal via OSD (Optimized Silent Drive); AF/MF switch