Comparison of Zeiss 50mm f/2 Loxia 2/50 and Pentax SMC P-FA 50mm f/2.8 Macro

Attribute	Pentax SMC P-FA 50mm f/2.8 Macro ×	Zeiss 50mm f/2 Loxia 2/50 ×
Closest Focus (m)	0.15	0.45
Magnification Ratio (x)	1	0.14
Length (mm)	71	59.2
Focus Details	-	Manual focus only, with large 180 degree focus throw, engraved distance and DOF scales
Diagonal Angle of View (degree)	47.00	46.80
Diaphragm Blades	-	10
Image Circle	35mm	35mm
Aperture (f)	2.80 - 32.00	2.00 - 22.00
Name	Pentax SMC P-FA 50mm f/2.8 Macro	Zeiss 50mm f/2 Loxia 2/50
Brand	Pentax	Carl-zeiss
Weight (g)	386	320
Type	Standard Prime Macro	Standard Prime
Lens Construction	8 elements in 7 groups	6 elements in 4 groups; Zeiss T* anti-reflective coating
Filter Size (mm)	52	52
Focal Length (mm)	50.00	50.00
Notes	-	Sony E-Mount (full frame); Weather-resistant lens mount gasket; Included Accessories: Lens hood, front and rear lens caps, de-click key.
APS Equivalent	75mm	1.5x: 75mm
Diaphragm Blades Type	-	rounded
Diameter (mm)	67.5	62.1