The Jupiter-9 85mm f/2 is a Soviet optical instrument derived from the pre-war Carl Zeiss Jena Sonnar design, manufactured at the KMZ factory and exported in modest quantities under the Jupiter brand. Optically, it inherits the Sonnar formula’s characteristic rendering: a smooth background blur without the Helios 44-2’s swirling tendencies, strong center sharpness with a gradual rolloff toward the edges, and a color rendering — particularly in the green channel — that has a coolness contemporary photographers find refreshing after years of the warm-biased output from modern lens coatings.