Also, when focused to infinity, the lens does not quite make it to the inifinty marking on the lens when it hits it's limit.
Anyway, I've shot the ruler at 1.1, 1.4, 2, 2.8, 4 and 5.6 at both the limit of the lens, and the actual "1" meter marking. I'll hopefully get the film processing tomorrow and be able to report back.
I was recommended Malcolm Taylor to look at this lens/camera, has anyone any experience with him? I'd like a fast turnaround, and a repairer who can look at both the lens and the body and find out which is at fault here.
And thanks again to Neare for explaining the ruler process, I think I managed it OK...