Its brilliance and quality of resolution are exemplary even at full aperture. Light falloff is very low. Its fast aperture, for a 90 mm lens, lets you shoot at relatively short exposure times even in dim light, helping to minimise the effects of camera shake, for instance when photographing street scenes from a distance.
This lens is unique because apochromatic correction and an aspherical surface are combined for the first time. Two of the five lens elements are made of high-refraction optical glass, and two others make judicious use of anomalous partial dispersion. Brilliance and resolving power are already outstanding at full aperture. Artificial vignetting is extremely low. These features lead to superlative results – in every application: such as portraiture, reportage or studio photography. In addition, its compact design and high speed make it ideal for hand-held photography.