Post by olddocfox on Oct 11, 2015 19:19:24 GMT -5
I purchased an inexpensive ($7.89 including shipping!) FOTASY M39 to m4/3 adapter from Rainbowimaging via Amazon.com. I wanted to try hanging my 50 mm f/3.5 Leitz Elmar and Zorki Industar lenses on my GX7 to compare them against one another and against more modern lenses. The adapter arrived on schedule and appeared to be very nicely made of chrome-plated brass and black anodized aluminum. I was initially pleased with my purchase.
However, a serious flaw became immediately evident. The adapter would not let the Leica infinity-lock release button be depressed.
Hence the lens could not be used out to infinity, even though the mount was properly registered from the film plane.
I fixed this using a fine-cut flat file. I filed a (file width) notch about 1/16" deep at the seven o'clock position (relative to the red mounting dot).
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The job took about half an hour. I used a mounted L39 lens to mark the desired location. Then I loosened the three set-screws (requires 2 mm jewler's screwdriver) retaining the rotatable inner brass ring and removed it. I clamped the aluminum part of the adapter down to my bench using hardwood blocks and small C-clamps. I used a fine-toothed flat file (with non-cutting edges) to make the notch. I worked slowly and carefully to make the notch even and smooth. Then I filed bevels at both edges to protect the lens-mount parts.
I carefully cleaned all of the aluminum filings away and reassembled the adaptor (with the inner ring loose). With a lens screwed into the inner ring, I rotated the inner ring clockwise to position the infinity lock release button at the edge of the slot as shown below. Then I tightened the three set-screws.
This worked just fine, allowing both my Elmar and Industar to work smoothly to infinity. Note that the rotational phasing of the two lenses is different. This requires adjusting the rotational position of inner ring when changing lenses.
Some photographic results from these lenses will follow, of course. I may even blow a little black paint over my file work.
However, a serious flaw became immediately evident. The adapter would not let the Leica infinity-lock release button be depressed.
Hence the lens could not be used out to infinity, even though the mount was properly registered from the film plane.
I fixed this using a fine-cut flat file. I filed a (file width) notch about 1/16" deep at the seven o'clock position (relative to the red mounting dot).
The job took about half an hour. I used a mounted L39 lens to mark the desired location. Then I loosened the three set-screws (requires 2 mm jewler's screwdriver) retaining the rotatable inner brass ring and removed it. I clamped the aluminum part of the adapter down to my bench using hardwood blocks and small C-clamps. I used a fine-toothed flat file (with non-cutting edges) to make the notch. I worked slowly and carefully to make the notch even and smooth. Then I filed bevels at both edges to protect the lens-mount parts.
I carefully cleaned all of the aluminum filings away and reassembled the adaptor (with the inner ring loose). With a lens screwed into the inner ring, I rotated the inner ring clockwise to position the infinity lock release button at the edge of the slot as shown below. Then I tightened the three set-screws.
This worked just fine, allowing both my Elmar and Industar to work smoothly to infinity. Note that the rotational phasing of the two lenses is different. This requires adjusting the rotational position of inner ring when changing lenses.
Some photographic results from these lenses will follow, of course. I may even blow a little black paint over my file work.
