Wide-angle prime lens for Exakta mount cameras.
The Carl Zeiss Jena Flektogon 20mm f/4 is a wide-angle lens produced by VEB Carl Zeiss Jena for the Exakta bayonet mount. The Flektogon formula is a retrofocus (reverse-telephoto) design allowing the rear element to clear the SLR mirror box. The 20mm Flektogon is regarded as one of the finest super-wide lenses produced in East Germany, with close-focus capability and excellent edge performance.
20mm focal length, f/4 maximum aperture, Exakta bayonet mount, Flektogon retrofocus formula, multi-coated (MC), close-focus capability (down to 20cm).
The Flektogon 20mm f/4 is a cult lens among adapted-use photographers, prized for its unusual close-focus ability (20cm minimum distance), micro-contrast, and characteristic East German rendering. Adapted to mirrorless cameras it is used for both landscape and creative close-up photography. The Exakta mount version can be adapted with available third-party adapters.
Inspect for fungus, haze, and T-coating condition. Test the close-focus mechanism — the helicoid's close-focus range is its most prized feature. Confirm Exakta bayonet engagement. Check aperture blades for oil contamination.