This lens from the famous German optical company, makers of the famous “Bubble Bokeh” Trioplan 100mm f2.8 lens, was introduced as a fast normal lens with close focusing capability for the Exakta camera in the 1960s, being able to focus to 1:2. It is a standard double gauss lens, butm in the words of one site: “It is an ambitious work in which three of the six elements are made of high-refractive-index crown glass with a refractive index of over 1.645 , which was still epoch-making at that time.” It was made for several years only, being replaced by a cheaper and faster Oreston f1.8. This lens is therefore rare, and has a unique bokeh focused at mid distances that makes it much sought after.
