Apochromatic color correction and an aspherical lens surface are combined for the first time in this lens of this type. Of its five individual elements, two are made of high-refraction glass, while two others feature anomalous partial dispersion. Its brilliance and quality of resolution are exemplary even at full aperture. Light falloff is very low. Its fast aperture for a 90mm lens lets you shoot at relatively short exposure times even in dim light, helping to minimize the effects of camera shake, as when photographing street scenes from a distance.
Angle of view (diagonal, horizontal, vertical): 27°, 23°, 15°
Optical design
Number of elements / groups: 5 / 5
Focal length: 90.9 mm
Entrance pupil: 58.6 mm (related to the first lens surface in light direction)
Focusing range: 1 m (3.3 ft) to Infinity
Distance setting
Scale: combined meter/feet-increments
Smallest object field: 220 mm x 330 mm
Highest reproduction ratio: 1:9
Diaphragm
Setting / Type: Preset, with clickstops (including half values), manual diaphragm
Smallest aperture: f/16
Bayonet: Leica M quick-change bayonet
Filter (type): internal thread for screw-in type filters E 55
Lens hood: Built-in, telescopic
Dimensions and weight
Length: 78 mm / 3.1 in
Largest diameter: 64 mm / 2.5 in
Weight: approx. 500 g / 17.6 oz (1.1 lbs)
