This is a postwar sample and therefore is coated, I wonder how different it would perform if it were not. This is I believe a seven element design in 6 groups, and therefore you have 12 air to glass surfaces that without coating would likely be very low contrast like that of the earlier 50mm f-2 Summar. I am aware that there is more complexities to it than simply calling it the predecessor, the double gauss design originated with Alvan Clark in 1888 and is only named as such because it uses the original gauss design which was duplicated and placed symmetrically about the aperture, identifying it as a symmetrical meniscus lens assembly to differentiate it from other lenses at the time which used symmetry. It was really Paul Rudolph with his Zeiss Planar who made the Double Gauss layout into what we know it today when he made his central negative elements larger to reduce the air space between them to reduce aberrations.