Comparison of Pentax 40mm f/2.8 Limited HD DA and Sony E 20mm f/2.8 SEL20F28

Attribute	Pentax 40mm f/2.8 Limited HD DA ×	Sony E 20mm f/2.8 SEL20F28 ×
Magnification Ratio (x)	0.13	0.12
Filter Size (mm)	49	49
Focus Details	"Quick Shift" AF/MF mechanism	Autofocus with stepper motor (quiet AF for movie capture); Direct Manual Focus supported.
Closest Focus (m)	0.4	0.2
Lens Construction	5 elements in 4 groups	6 elements in 6 groups, includes 3 aspherical surfaces
Length (mm)	15	20.4
Focal Length (mm)	40.00	20.00
Diaphragm Blades Type	rounded	rounded
Brand	Pentax	Sony
Image Circle	APS-C	APS-C (Sony E-Mount)
Name	Pentax 40mm f/2.8 Limited HD DA	Sony E 20mm f/2.8 SEL20F28
Weight (g)	89	69
Type	Standard Prime	Wide Prime
Notes	Available in black or silver; High-grade multi-layer HD (High Definition) coating; Rounder aperture blades should yield more pleasing bokeh.	Sony E-Mount. Included Accessories: front and rear lens caps.
APS Equivalent	61mm	30mm
Aperture (f)	2.80 - 22.00	2.80 - 22.00
Diaphragm Blades	9	7
Diagonal Angle of View (degree)	39.00	-
Diameter (mm)	63	62.6