Contax/Kiev internal bayonet lens to M52x1 thread adapter for helicoids

This adapter allows mounting a lens with internal Contax/Kiev bayonet onto Chinese M52x1 focusing helicoid.

Full required setup consists of:

1. This adapter.
2. Chinese M52x1 female to M42x1 male focusing helicoid with 17-30mm extension range (we don't sell them).
3. Our short M42x1 to MFT adapter (infinity-allowed M42 adapter will not work).

Such setup is quite weird as you can see on the pictures, but it does necessary job providing focusing from about 20 cm to infinity. Tested with Helios-103 lens.

For sale in this listing is the Contax to M52x1 adapter only.

Below is report from one of our customers:

The adapter works well with all of the 50mm internal-mount Contax/Kiev lenses I own. There's one important difference between the collapsible lenses and the rigid lenses – the rigid lenses seat differently against the face of the adapter, because they're designed with flared barrels. Because of that, the rear element of the lens, when installed in the adapter and fitted to the helicoid, is further away from the sensor than the rear element of the collapsible versions. (For the rigid lenses, the tab on the lens doesn't go all the way to the bottom of the notch in the adapter.)

None of this is a problem – it just means that some fine-tuning (adding/removing extension) is necessary for infinity focus and best close focus. And anybody who's using this adapter should already be experienced with that kind of adjustment.

Specifically, my 1959 rigid Jupiter-8 and my rigid West German Sonnar 50/1.5 are exactly the same in terms of necessary extension. My rigid Helios-103, however, sits a little closer to the sensor. There's probably a certain amount of variation among the various rigid lenses.

I also needed to remove two tiny screws from the barrel of the Helios-103 to make it fit in the adapter. Removing the screws doesn't seem to have affected the lens in any way, and they can always be reinstalled if necessary.

My collapsible Zorki 50/2 and prewar Sonnar 50/2 are exactly the same in terms of their position in the adapter.

Anyway, I hope that might be helpful in answering any questions from buyers. I'm very happy with the adapter – I find it easier to focus these lenses with the 52mm helicoid than with a "correct" helicoid built like the original Contax/Kiev design. And the close focusing is really a huge benefit.