SUMMARY
Presenting a favored focal length for portraiture, the APO-Summicron-SL 90mm f/2 ASPH. from Leica is an optically refined short telephoto prime designed for full-frame L-mount mirrorless cameras. Complementing the comfortable focal length is a bright f/2 maximum aperture that suits working in low-light conditions and also affords great control over depth of field for isolating subject matter. The lens' apochromatic optical design uses anomalous partial dispersion glass to suppress color fringing and chromatic aberrations for high clarity and color accuracy, and one aspherical element is also featured to reduce spherical aberrations for improved sharpness. Multi-layer coatings have also been applied to limit flare and ghosting for increased contrast when working in strong lighting conditions. Complementing the optical assets is a Dual Syncro Drive stepping motor, which delivers fast and quiet autofocus performance, and a floating elements system maintains consistent imaging quality throughout the focusing range. Additionally, an AquaDura coating has been applied to the exposed elements and seals have been incorporated in the lens design to benefit working in harsh environmental conditions.
HIGHLIGHTS
Portrait-length 90mm f/2 lens is designed for full-frame Leica L-mount mirrorless cameras, however can also be used with APS-C models where it provides a 135mm equivalent focal length.
Bright f/2 maximum aperture benefits working in low-light conditions and also affords greater control over depth of field for working with selective focusing techniques.
One aspherical element is used to reduce distortion and spherical aberrations for improved sharpness and accurate rendering.
Apochromatic design employs anomalous partial dispersion glass to suppress chromatic aberrations throughout the aperture range for increased color accuracy and clarity.
Multi-layer coatings have been applied to individual elements to suppress surface reflections, flare, and ghosting for increased contrast and color fidelity.
Dual Syncro Drive stepping motor delivers quick, precise, and near-silent autofocus performance to suit both photo and video applications. This system also avails full-time manual focus override.
Floating elements system and an internal focusing design maintain consistent image quality throughout the focusing range, from 2' to infinity.
Water-repellent AquaDura coating has been applied to the front and rear optical surfaces to protect against moisture and other elements.
Weather-sealed design protects against dust and moisture to benefit working in inclement shooting conditions.
