The Nokton 50/1.5 Asph LTM and V1 M-Mount: modernized Double-Gauss with aspheric optics. 6 elements in 5 groups, the classic Canon 50/1.4 is 6 in 4. Most classic f1.4 lenses are 7 elements. The LTM 50/1.5 Nokton Asph goes for about the same as the Canon in clean condition. Read: it's a steal...