In the 1940s, Leitz decided to develop a faster lens for the 90 mm focal length range, aiming to significantly exceed an aperture of f/2. The open aperture performance of the Summarex 85 mm f/1.5 was, by default, disappointing. So instead of developing this lens further, Leitz turned their attentions to the construction of a 90 mm Summicron – whose initial aperture of f/2 was a more realistic starting point for what the company were aiming to achieve. For this reason, 90 mm became one of Leica's most popular focal lengths along with 35 and 50 mm.
With a picture angle of 27 degrees, a 90 mm lens encourages the photographer to focus on the essentials. The shallow depth of field at wide aperture allows for an excellent isolation of the object from the background. And when shooting portraits, a 90 mm FL creates a pleasing distance to the subject.
Launched in 1998, the Apo-Summicron M 90 mm f/2 Asph is one of the most highly-performing lenses ever constructed. The first lens to combine chromatic correction with an aspheric lens surface, it offers exceptional brilliance even at fully open aperture.