The optical performance and functions of the silver lens are equivalent to those of the black standard lens for Leica rangefinder cameras.
The LEICA SUMMILUX-M f/1.4/50mm ASPH. is the first Leica M objective to integrate a floating element: During focusing, the last lens element changes its position in relation to the rest of the optical system. The result is superb optical quality right down to the macro range. To attain the same high quality of imaging over the whole image field, the LEICA SUMMILUX-M f/1.4/50mm ASPH. incorporates high-refractive glass types and two with anomalous partial dispersion, one of which originates from the former Leitz Glass Laboratory.
The new LEICA SUMMILUX-M f/1.4/50mm ASPH. performs consistently well at all apertures and focus settings. At full aperture, the lens produces high-contrast images of even the most delicate structures. This magnificent performance can only be enhanced slightly by stopping down. Another of the lensí strengths is the practically distortion-free imaging. The vignetting in the corners of up to two stops, which is usual with such fast lenses at full aperture, is distinctly reduced by stopping down: at aperture 5.6 to about one stop. Also, the use of state-of-the-art coating technology ensures an excellent standard of reflection prevention.
The LEICA SUMMILUX-M f/1.4/50mm ASPH. has a built-in telescopic lens hood that protects the lens from stray light or dirt and can be locked in the extended position to prevent it being pushed in inadvertently. As well as the accustomed knurled ring, the lens has a recessed grip for particularly convenient one-finger focusing. The well-balanced proportions of the lens encourage hours of fatigue-free photography.