The Schneider Angulon is a six element Dagor type lens in two fully cemented groups. A tessar type lens can only bring an angle of view of max 80°. The Angulon up to 105°Frankly, I'd get one of the f8's -- as sharp, as easy (or difficult) to focus and half the weight. Again, the Schneider 90 f6.8 is an older Tessar design, not a more modern plasmat.