Monday, October 13, 2014

How to Mount the Xenon 50mm f2 from Diax IIb to NEX

macman asked how the Xenon 50mm f2 is adapter to the NEX in the last post so I have decided to write a post on how it's done, which is extremely simple.  This approach is applicable to the Retina-Xenon 50mm f2 I wrote about it here, once you have taken it out of the camera.

To use the lens, you will need the following:

  • Focus Helicoid, or an extension tube of about 35mm with a 52mm opening.  Since the lens has it's own focusing mechanism, the focus helicoid is useful to make focusing closer than using just the extension tube, but is not necessary.  However, for the Retina-Xenon, you will need the focus helicoid since the focusing mechanism is not there anymore.
  • A 52mm filter with the glass removed.  This filter ring will be glued to rear of the lens, which in turn will be screwed onto the focus helicoid or extension tube.
  • Epoxy of some kind.  I use J-B Kwik since it's strong enough, but if reversal is needed, I can cut the filter ring and the glue will come off with some force.  J-B Weld is much stronger and harder to remove later.
The 52mm filter ring is just slightly smaller than the rear of the lens.  You will need to sand off about 1/2 a millimeter inside the filter thread, like the picture below:

Sand off the threads inside the filter ring.  Click for larger.

Once the filter fits over the rear of the lens, apply epoxy in the inside of the filter ring, and then fit the filter ring over the rear of the lens.  Be sure the filter ring sits evenly.  Let the epoxy set.  If done correctly, it should look something like the picture below:

Filter ring attached.  Cick for larger.

Once the epoxy is set (I usually leave it over night), you can then mount the lens to either the extension tubes, or the focus helicoid:

Lens on Helicoid.  Click for larger.

The lens is now ready to use.  Mount it on the camera and enjoy!  If you have any questions, ask it in the comments section below.  I will answer as best as I can.

Ready to shoot.  Click for larger.


  1. Nice work! Is the focusing helicoid m42 at the end?

    1. Hi, yes. I used this M42-E-mount adapter for the helicoid: