There is an detailed German instruction online on our website: https://3druck.com/blog/diy-anleitung-bessere-mondfotos-mit-3d-gedruckten-hilfsmitteln-3155194/

And here is the shorter english version:
With the two included objects it is possible to get better pictures of the moon, at least it was for me. I have used a Nikon D3200 and an old 500mm M42 catadioptric system that I have bought for only a few bucks.

The spacer part is designed to create a bigger distance between the catadioptric system and the camera. In my case it was needed because the hot shoe of the camera collided with the catadioptric system. Depending on your camera and M42 mount you may not need this adapter or change properties (therefore I uploaded it as SCAD file too).

The second part is the more important one: It’s a Hartman Mask (also called Scheinerblende) and helps you to exactly focus on very distant objects like the moon. Just put it in front of your Camera and try to focus – you will see your target object double. When it is in focus you will see it clearly and not double any more. I added two example pictures one with the moon out of focus und one with the moon just in focus. The mask is also customizable because depending on your optic system you may need other diameters.

Like for all Thingiverse projects either the creator nor 3Druck.com are responsible for any demages that these 3D printed parts may cause.