This lens is a beauty. Let me tell you something about its background:
It was designed and calculated by famous Leitz lens designer Max Berek, who by the way worked as a honorary professor at the Philipps-Universität Marburg, the uni I also work for as a lecturer. 😉
In its line of ancestors we find widely known Double-Gauss-Lenses such as Planars, Xenotars or Xenon-type calculations. The Summarit is a 7-lens-in-4-elements design, a Gauss-type with a cemented front element. This design has even been named “Summitar-type”. Lenses such as Voigtländer Nokton or the first Leica Summicron follow this design as well. The Summitar-type was succeeded by the Ultron-type or its enhanced variations.
Two important designs of fast “normal” lenses have always competed against each other: the Sonnar-type (derived from the classic triplet) and the Double-Gauss-type. These lens schemes perhaps show the basic design differences:
Zeiss Sonnar and the very similar Russian lens Jupiter-8 2.0/50:
And the Summitar-type with the next in line, the first version of the Summircon, which did not have a cemented front element any longer:
It will be very interesting to see how different the Jupiter-8 and the Summitar 2/5cm render images. A comparison, I plan to do soon…
More information about lens design here: