Based on a classic design from 1952, the black C Biogon T* 21mm f/4.5 ZM from ZEISS is a super wide-angle prime for M-mount rangefinder cameras. Its 'C' designation reflects the lens's compact form factor and classic optical design to produce imagery with true color fidelity and natural rendering. The Biogon optical concept helps to ensure virtually no distortion, and this eight elements, six groups layout also maintains a high degree of sharpness and clarity. Additionally, a T* anti-reflective coating has also been applied to reduce lens flare and ghosting for improved contrast in strong lighting conditions.
Type
'C' lens refers to this lens's classic aesthetic and compact design
that recalls its predecessor from 1952. The glass and coatings have been
updated to contemporary standards, however it still produces a timeless
look well-suited for both film and digital use.
Biogon
optical concept benefits the super-wide focal length by helping to
virtually eliminate distortion for clean, realistic rendering.
Zeiss
T* anti-reflective coatings have been applied to each lens surface to
help minimize reflections in order to provide greater image clarity,
contrast, and color fidelity.
Manual focus design enables a minimum focusing distance of 1.6'.