Leica 21mm f/3.4 Super-Elmar-M ASPH. Lens for M-Mount, Black Anodized Finish, 6-Bit {E46} 11145

Leica's 21mm super-wide: compact rangefinder geometry, serious optical engineering.

At 43mm long and 279g, the Super-Elmar-M 21mm f/3.4 ASPH. fits the M-system ethos without compromise. The optical formula runs 8 elements in 7 groups, with a double-sided aspherical element doing the heavy lifting for compactness and aberration control, backed by four anomalous partial dispersion elements that keep chromatic fringing in check across the frame. The 91-degree diagonal angle of view on full-frame is genuine super-wide territory, and the lens holds contrast and detail from f/3.4 through f/16, with half-stop aperture clicks giving deliberate exposure control.

Built from metal throughout, with a 46mm non-rotating filter thread, a depth-of-field scale, and a distance scale on the barrel, this lens is set up for the way rangefinder photographers actually work: zone focus, hyperfocal distance, pre-visualization. The 6-bit coding communicates lens data to Leica M digital bodies for accurate EXIF and automatic vignetting correction. A metal screw-mounted hood ships in the box. M-mount adapters open this lens to Sony E, Nikon Z, Canon RF, and L-Mount bodies, but the barrel controls and manual-only focus make it most at home on the platform it was designed for.

Who It's For

Travel and street photographers who shoot M-film bodies or digital M cameras will find the 279g weight and 43mm length genuinely unobtrusive on a day-long walk. Architectural and urban landscape shooters get the 91-degree diagonal angle of view with distortion kept to a minimum by the aspherical optical design. Documentary and photojournalist shooters benefit from the depth-of-field and distance scales, which allow fast zone-focus work without lifting the camera to eye level. Adapting to mirrorless systems like Sony E or L-Mount gives wide-angle macro and landscape photographers access to a proven optical formula with full manual aperture ring control.

Key Features

• 8 elements in 7 groups with double-sided aspherical element
• f/3.4–f/16 with half-stop aperture detents
• 91° diagonal angle of view on full-frame
• Four anomalous partial dispersion elements for chromatic aberration control
• Manual focus only, 0.70m minimum focus distance
• Leica M-mount, non-rotating 46mm filter thread
• Depth-of-field and distance scales on barrel
• 6-bit coded for M digital body compatibility
• 43mm length, 279g weight, all-metal construction

FAQ

What's the angle of view on a full-frame M body versus an M8?

On full-frame (24x36mm), you get 91° diagonal. On M8 (18x27mm), it drops to 74° diagonal - a significant difference that matters for composition planning.

How does the double-sided aspherical element affect optical performance?

It allows Leica to compress the design to 43mm while controlling spherical aberration and distortion across the aperture range. You get edge sharpness and contrast from f/3.4 through f/16 without the length penalty of a conventional wide-angle design.

Can I use this on Sony E, Nikon Z, or Canon RF bodies with an adapter?

Yes, M-mount adapters exist for those mounts. The lens works mechanically and optically, but you lose the rangefinder focusing experience and the 6-bit coding becomes inert on non-Leica bodies. It's technically possible, but the design assumes an M-mount body.

What's the minimum focus distance, and how does the DOF scale help?

0.70m (27.56 inches). The DOF scale on the barrel lets you set hyperfocal distance without metering - zone focus the way rangefinder photography was meant to work. No autofocus, no live view needed.

Why does the filter thread not rotate?

Non-rotating threads are standard on M-mount primes for rangefinder work. You mount a polarizer or ND filter once and don't twist the lens during composition - the barrel stays locked to your distance and aperture settings.

How do the four anomalous partial dispersion elements control chromatic aberration?

They're engineered glass types that bend wavelengths more uniformly across the spectrum, minimizing color fringing at the edges and corners where conventional glass would struggle. Results in cleaner detail edge-to-edge.

Does the 6-bit coding do anything practical on film M bodies?

No - film bodies can't read it. It communicates lens data to Leica M digital bodies (M9 and later) for accurate EXIF metadata and automatic vignetting correction in the software.