I’m looking at machining some male EF lens mount flanges to convert some lenses from another mount and thought I’d see if anyone here has experience or interest in doing this!
With the HAAS being 3 axis only, this could prove to be a challenge.
What mount are you trying to come from?
I understand the fun in making stuff just to make stuff, but you can probably buy the flanges on eBay or elsewhere online and concentrate your machining skills on the rest of the adapter ring…
Sony A-mount / Minolta AF-mount. The flange focal distance is only 0.5mm greater on EF so I think I can just make the base of the flange 0.5mm thicker to get the right distance.
I am currently considering two approaches:
(1) Use the HAAS for the basic shape, followed by a lathe to manually remove the material below the tabs that the HAAS would not be able to reach.
(2) Use a lathe for the basic shape and a circular table with the Bridgeport to clear out the spaces between the tabs and make the holes in the base.
@jswilson64—I would prefer to just buy flanges (and have considered modifying an extension tube flange), but have not found one that would be a perfect fit for my lenses. These are manual Rokinon lenses, and it appears likely that the only difference between the EF and A models is the flange.
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I’m not sure it’s feasible without optics. Having just a .5mm flange-back differential isn’t going to be a workable solution.
I have considered those adapters, but am concerned about the optics.
The approach I am considering is not to adapt the flange, but to replace it. The current flange has a 2.5mm-thick base, so making an EF flange with a 3mm-thick base should put the lens in the right position.
Here are a couple of pictures of a Sony A / Minolta AF flange from a Rokinon lens.
Can you simply make a 1/2mm shim?
Yes, but the mount is different (Canon EF vs Sony A). The 0.5mm actually might not make much difference—I might not be able to focus quite as closely, but that wouldn’t be a huge problem.