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How about a $2500 dig back.....


New Member
Does this sound interesting........

34mm x 34mm
So 1.6 crop factor

Works with v series blad lenses.

Here is what I've discovered........

I took my 150mm lens, fitted it to my c/y adapter, fitted that to my Metabones SpeedBooster, used a piece of paper to measure the image circle.

I got 34mm.

So a quick bit of maths says I can fit a 24mm square inside that, or a nice 1:1 crop on a 36x24mm FF sensor.

Now if I take that lens and adapter combination and attach it to a Sony A7r.......

And crop the resultant image to a 1:1.......

I'll have the equivalent of a 24MP digital back with a 34mm square sensor, or a 1.6 crop factor.

This assumes that my crude measurement of the image circle is correct. Since I don't have a Sony A7r to try it with.

The SpeedBooster is a focal length reducer with a 0.71 factor, for those that don't know.


Well-Known Member
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It's been a while since I've been on this site and posted anything, but I saw this message and thought it interesting that you haven't purchased an adapter for the DSLR you currently own, if you own one that is. I have one for my Nikon D700 and I use the Hasselblad 180mm quite a bit and the 120mm. The combo works pretty well.

I still wish for a 6x6 sensor back to come out, but at this point that will never happen. I know, never say never, but in this case I'm pretty sure it won't. Good luck.