Comparison of Fujinon XF 16mm f/2.8 R WR and Pentax SMC P-DA 21mm f/3.2 AL Limited

Attribute	Fujinon XF 16mm f/2.8 R WR ×	Pentax SMC P-DA 21mm f/3.2 AL Limited ×
Magnification Ratio (x)	0.13	0.17
Filter Size (mm)	49	43
Focus Details	Inner focusing system with stepper motor	"Quick Shift" AF/MF mechanism
Closest Focus (m)	0.17	0.2
Lens Construction	10 elements in 8 groups, including 2 aspherical elements	8 elements in 5 groups, including 1 hybrid aspherical element
Length (mm)	45.4	25
Focal Length (mm)	16.00	21.00
Diaphragm Blades Type	rounded	-
Brand	Fujinon	Pentax
Image Circle	APS-C (Fujifilm X-mount)	APS-C
Name	Fujinon XF 16mm f/2.8 R WR	Pentax SMC P-DA 21mm f/3.2 AL Limited
Weight (g)	155	140
Type	Wide Prime	Wide Prime
Notes	For Fujifilm X-mount; Weather and Dust Resistant; Lens hood included.	Dual filter attachment design: 43mm filters on the hood, and 49mm filters on the lens (without use of the hood).
APS Equivalent	24mm	31.5mm
Aperture (f)	2.80 - 22.00	3.20 - 22.00
Diaphragm Blades	9	7
Diagonal Angle of View (degree)	83.20	68.00
Diameter (mm)	60	63