can somebody give me information about Mamiya Sekor f/3,7 80mm for Mamiya TLR cameras. I recently bought one in like new conditon. This was cheaper than prime lens f/2.8 80mm and it be placed shor time as set lens with Mamiya C 220 bodies. I cannot find any serious information about this lens. Does anyone know the optical design? It is Tessar type? Can anyone compare it with normal f2, 8 80 mm (sharpness, etc.)?