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Hello all,
I know this is a very weird question and I am pretty sure that the answer will be 'no such thing exists without creating it as a custom build just for you'!
I make use of the 645 1.4x converter with the 645 600mm f5.6 A lens. I also have the 67 1.4x converter, which I have used with the 67 400mm f4 EDIF lens (amongst others). I have the impression that the 67 converter is optically superior (though I can't prove it) - this is based on usage in cases where I can use either converter (i.e. when using converters with 67 lenses on the 645Z/D). I wish I could use the 67 1.4x converter with the 645 600mm lens. But that would involve having a mount adaptor that works in the opposite direction to the usual - in other words, converting the lens mount UP in size rather than down, so that I can mount a 645 lens on a 67 1.4 converter (which, of course, is then converted back
down in size to be mounted on the 645Z/D). I am guessing, since there wouldn't be much call for such a device, that it doesn't exist. Unless someone knows better......?
Ed
Last edited by Ed Hurst; 11-08-2020 at 09:36 PM.