This special lens design features an aspherical lens surface, giving this compact unit outstanding contrast and detail rendition even at full aperture. An accessory brilliant viewfinder #12019 is needed for checking the field of view, whereas focusing and exposure metering are performed through the camera's own viewfinder. This high-performance lens also makes it possible to work efficiently in cramped quarters. It adds a more dynamic feeling to close-up pictures and it gives landscape photographs significantly more depth.
This lens has been updated with the "6-bit" coding, which allows the digital M camera to read this information optically and to identify which lens is being used. The camera can then (optionally) apply a "final stage" software based vignetting correction (for RAW images the lens used is simply recorded, no change is made).