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Sony ring light

Yes, Pete's correct in what he says. I used to have the old Minolta Ring Flash (very different to Sony's Ring Light) and currently have a Sony Macro Twin Flash - both were supplied with 49 & 55mm adapters to fit the Minolta/Sony macro lenses which have/had filter threads of those sizes. I have used both with an old Tamron 90mm lens using a step down ring to 52mm without any problems. As Pete says with larger threads you may encounter vignetting problems.
Somewhere at the back of my mind I seem to recall that a larger adapter could be obtained from Sony (think it was 72mm) Might be worth having a look at Sony's web-site or possibly at this is it:
link
Although of course this may not fit the Ring Light - The guy at Minolta Mania (think he's called Paul) should be able to tell you one way or the other.
Regards, Peter
Somewhere at the back of my mind I seem to recall that a larger adapter could be obtained from Sony (think it was 72mm) Might be worth having a look at Sony's web-site or possibly at this is it:
link
Although of course this may not fit the Ring Light - The guy at Minolta Mania (think he's called Paul) should be able to tell you one way or the other.
Regards, Peter