Leica M 2/50mm Black APO-Summicron-M ASPH. 11141 Sealed Unopened 2023 Production. Production March 2023. In addition to the apochromatic designation, this lens also pairs a Gaussian type optical construction in front of the aperture along with a design resembling the Summilux-M 50mm f/1.4 behind the aperture, in order to significantly reduce distortion while also increasing overall sharpness and consistent illumination.
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