I called this product "Astroschelle" because "Schelle" is the German word for 'tube ring'. It is a combination of a lens holder based on tube rings and a dovetail adapter for astronomical mounts. It reduces greatly the mechanical stress of the camera bajonett and helps to avoid tilt issues. They are often caused by a small tilt of the lens to the image sensor when the lens is simply attached to the camera body without any further support.
The camera can be rotated in any angle to select the best field of view for a perfect image composition. For a better orientation there are some coarse angle marks on the tube ring.
As a first step you have to insert the two screw nuts into the designated slots of the locks. You may use a small tool to push it completely into the lock. If you look throught the 4mm hole, you shall see the nut's thread. (There's also a small hole on the outside of the lock for removal of the nut.) That's it!
Then you can put your lens into the opened holder and close the holder. The thicker tube ring is closer to the camera. Then use the two screws to fix the lock. Be careful to hold the lens until the two screws are fixed!
As a member of the OSHWA I'm totally convinced of the idea to offer products as Open Source Hardware instead of protecting them by patents. The OSHWA (Open Source Hardware Association) is one of the most well-known organizations that support the open-source-hardware ideas.
This lens holder is also based on an Open Source Hardware project hosted by me at Thingiverse:
As of Aug 08 2017, this holder is now a certified Open Source Hardware with the UID DE000004! It is now officially listed in the OSHWA certification directory. One of the most important aspects of the OSHWA certification is to publish the source code of the design files. It can be found at GitHub (OpenSCAD format):
You are invited to work on this project, if you have any ideas or solutions for an issue. I'm always pleased to get some input, whatever to criticize is (I'm open to both positive and negative critics!). GitHub contains a pretty good issue tracker, you may enter your suggestions or issues there directly! The item offered here is produced using the following commit version: Version 2.3
Copyright Notice: SAMYANG is a trademark of SAMYANG OPTICS CO., LTD. VIXEN is a trademark of VIXEN CO., LTD.
Disclaimer: I am not licensed, approved or endorsed by Samyang or Vixen