Distinguished by its optically refined design, the black APO-Summicron-M 75mm f/2 ASPH. from Leica is a bright portrait-length lens for M-mount rangefinder cameras. Its apochromatic designation is a result of the use of anomalous partial dispersion glasses to virtually eliminate color fringing and chromatic aberrations, as well as an aspherical element made from high refractive index glass to further control spherical aberrations for notable sharpness and clarity. The lens also employs a rear floating element to maintain image quality throughout the focusing range, even at the minimum focusing distance of 2.3'. Additionally, the compact lens also features a built-in extendable lens hood to shield the front element and the front is threaded to accept 49mm screw-on filters.
Apochromatic design employs one fluorite element and one anomalous partial dispersion glass element to virtually eliminate chromatic aberrations and color fringing for improve clarity and color accuracy throughout the aperture range.
In addition to the apochromatic designation, this lens also pairs a double Gauss type optical construction in front of the aperture with a highly refractive glass aspherical element, and 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.
A floating element is used to maintain clarity and sharpness throughout the focusing range, especially at close range.
Bright f/2 maximum aperture benefits working in difficult lighting conditions and also affords greater control over depth of field.
Manual focus design provides a minimum focusing distance of 2.3' with a maximum magnification ratio of 1:7.
Built-in extendable lens hood shades and protects the front element to reduce lens flare and ghosting. Additionally, the front of the lens is threaded to accept 49mm screw-in filters.