I had acquired a 70-200 Nikkor which is a great lens, but it had no tripod socket (made for sports photography with Tri-X or some such), so I needed the extra speed for handheld tele shots. And the Kodachrome 200 looked okay when projected onto a beaded screen, which kinda covered up the grain. But when I started scanning the stuff years later....wow....just terrible. Compared with Kodachrome II that scans so well you almost think it is a digital original. Golly what great pix I cudda gotten in the 60's if I'd only had digital then......
JBWX