Cosina has announced the Voigtländer APO-Lanthar 90mm f/4 Close Focus, a manual-focus medium telephoto lens for Leica M-mount cameras. The lens was first shown as a prototype at CP+ 2026 in Yokohama in February and has now been fully detailed ahead of its August 2026 release.

The APO-Lanthar designation indicates Cosina’s highest tier of optical correction: the lens indeed uses an apochromatic design intended to bring red, green, and blue wavelengths of light to focus at the same plane, eliminating axial chromatic aberration across the frame. The optical formula comprises eight elements in six groups, with six of those eight elements made from abnormal partial dispersion glass — a ratio that is unusually high even by apochromatic standards and reflects the priority placed on aberration control. A 10-blade aperture diaphragm produces smooth out-of-focus rendering, with the aperture range running from f/4 to f/22.

The lens’s dimensions are its most immediately notable characteristic for rangefinder use. At 53mm in diameter and 54.8mm in length, it is substantially shorter and narrower than most 90mm M-mount lenses, including faster alternatives. Many longer M-mount lenses obstruct the rangefinder window at the point of coupling — the APO-Lanthar 90mm f/4’s compact barrel reduces this interference. Weight is 235 grams, and the front filter thread is 43mm. A compact dedicated metal hood is included, adding approximately 9mm when attached.

Close focusing is a defining feature of the design, as reflected in the name. Standard rangefinder-coupled lenses typically stop coupling at 0.7 meters; the APO-Lanthar 90mm f/4 extends this to 0.5 meters using a simple extension mechanism, with a tactile click stop at the 0.7-meter mark to indicate the rangefinder coupling limit. Beyond that point, focusing must be performed via electronic viewfinder or live view. Maximum magnification at the closest distance is 0.28x. The full-frame image circle makes the lens adaptable to mirrorless cameras via standard M-mount adapters.

Here are some sample pictures, courtesy of Cosina. All of them are shot by Takashi Koike: