The CFi50 is an all round, wide-angle lens. This lens is ideal for landscape, interiors, architectural, and documentary photography.
With its moderate wide-angle effect, the Distagon CFi 50 mm is a versatile all-purpose lens.
It incorporates modern optical design with floating lens elements (FLE) to ensure high performance even at the close focusing range.    
Corner-to-corner illumination is very even with all aperture settings, and distortion and stray light are extremely well controlled.

Technical:
Focal length 52.0 mm
Aperture range 4-32
Focusing range 0.5 m (1' 7") - infinity
Angle of view diagonal/horizontal 75°/57°
No. of elements 9 T*
Filters Ø70, also supplied with filter adapter ring 3040775 for use of one Ø60 filter
Weight 800 g (1 lb 12 oz)
Length 95 mm (3.75")