Mounted in a Sekio LS22 is a Carl Zeiss 3.5 100mm. s/n 4153922, the lens appears to be coated with very light scratches in the front element. The problem is that the sekio goes from F-8 to 64, but if you go past the f8 it will fully open to f3.5, just no numbers for reference. Would this mean that the shutter was made for a f8 lens? Kinda confused on how to handle this. The shutter works perfectly from 1 to 500 sec and has good X sync.