I've been experimenting and have found the AF140C ringflash seems to work fine with the 645. The only ringflash mentioned in the manual is the AF80C, presumably because this was the current model at the time. It does say that the only lens it will work with is the 75mm (with a 58-49mm step-down adaptor ring), and this is also the only lens mentioned in the AF140C manual.
So the question: will it be OK with the 120mm macro, which seems the obvious lens to use? I know a 67-58mm step-down adaptor will be required, but this is no greater than that for the AF80C and the 75mm. Will it introduce too much vignetting? Cheers Nick
