The Super Crisp, Super Wide-angle
This fast, super wide-angle lens allows photographers to experiment with different angles and perspectives. The Biogon T* 2,8/21 ZM offers outstanding performance and xtreme resolving power even when shot wide open, with virtually no distortion, excellent control of flare and ghosting and superb contrast rendition across the entire frame. The slim lens design is easy to grip and focus, and uses a standard 46 mm filter diameter similar to many of the other ZM lenses and allows filters to be interchanged between the lenses. The lens is rangefinder coupled for easy focusing and the optional 21 mm viewfinder is available for accurate image composition. Combined with a digital rangefinder camera with a 1.3 crop factor, the lens has an effective focal length of 27 mm. The Biogon T* 2,8/21 ZM is suitable for many different wideangle applications including reportage work, landscape and architectural photos.
Excellent image quality
The Carl Zeiss range of T* lenses offers the highest possible standards in terms of performance, reliability and, of course, image quality. Quite simply, they are superior in every way. You can count on highly advanced flare control for crisp and brilliant images, for example. And virtually zero geometric distortion, ensuring precise accuracy when reproducing shapes especially useful when photographing products and architecture.
Virtually distortion-free optics
Dramatic perspectives and a view from extraordinary image angles SLR lenses from Carl Zeiss 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.
Carl Zeiss T* anti-reflective coating
All lens elements in SLR lenses from Carl Zeiss feature the T* anti-reflective coating and an optical design that produces brilliant pictures even in unfavorable lighting conditions. We vacuum deposit very thin, transparent coats on the surfaces of the lens elements to make them anti-reflective. Special substances, one by one, are vaporized with very high energy in a high vacuum, which are then deposited on the glass surface as a coating with precisely controlled thicknesses to achieve the desired reduction of reflections. The first coatings were applied by Carl Zeiss back in the 1930s.
Excellent resolution and high contrast
Rich, vibrant colors are vital to creating a lasting impression. Stray light in the lens, however, would lead to a brightening of the image, which is particularly visible in shadow areas. Image contrast is lowered; the image appears dull and bleached. We combine various, elaborate techniques to reduce unwanted stray light.
Minimized Focus Shift
Carl 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.