|Focal length||25 mm|
|Aperture range||2.8 – 22 (1/3 steps)
|Focusing range||0.5 m – ∞
|Number of elements/groups||9/7
|Image ratio at close range||1 : 18|
|Coverage at close range||43 x 65 cm|
|Angular field, diag./horiz./vert.||82°/72°/52 °
||M 46 x 0.75|
|Dimensions (with caps)||ø 53 mm, length 71 mm
Dramatic perspectives and a view from extraordinary image angles – ZEISS lenses open up new composition possibilities. Distortion would disrupt the composition because straight lines, whose image does not go through the image center, would be reproduced with a curved shape. This annoying effect is accordingly and largely compensated through elaborate optical designs at all focal lengths.
ZEISS T*® ZM-mount lenses are specifically designed to minimize focus shift with aperture changes – an important innovation with big benefits for rangefinder photography. As a result, you can expect improved accuracy of the rangefinder-defined focus. While the precise 10-blade aperture with 1/3 stop interval click stops ensures exact exposure.
Manually focusing a lens means controlling the image result from your fingertips. A good ergonomic design makes all the difference. The user-friendly focusing ring on ZEISS lenses with an ergonomic finger rest is perfect for fast, precise focusing. Changes are immediately visible in the viewfinder. The high-quality focusing mechanism moves smoothly without play, thus also supporting the intuitive interaction with the focal plane.
The optical elements of ZEISS lenses feature T*® anti-reflective coating on all surfaces and an optical design that guarantees images of superior brilliance at all times, even in unfavourable lighting conditions. We apply the anti-reflective coating to the lens surfaces by the vapour deposition of extremely thin, transparent layers on the glass. In this process, special substances are vaporized with extremely high energy in a high-vacuum environment and are subsequently deposited on the glass surfaces, one after another, as layers with precisely controlled thicknesses to achieve the desired reduction of reflective properties. The first coating techniques were employed by ZEISS as long ago as in the 1930s.
The mount and control elements of all ZM lenses are made of metal and are designed for decades of intensive use. The high-quality craftsmanship of the all-metal mounts, the easy-to-grip metal focus and aperture ring and the robust front bayonet and filter threads ensure an amazing photographic experience.
"As for the Zeiss 25 Biogon, I have been wanting to try this lens for over a year. I have seen the results from it on the M8 and M8.2 and every time the image quality was stellar..."
"The Zeiss Biogon T* 2,8/25 ZM lens is sure to dazzle even the most stringent of lens critics and one that even Zeiss is proud of. It's capable of some remarkable resolution...."