Thread Ring Types
The Astroasis filter drawer uses two types of interchangeable rings to configure either a male or female thread on each side of the drawer:
- M-type rings – Create a male thread. These are typically used on the camera side or when connecting to camera-side accessories.
- F-type rings – Create a female thread. These are normally used on the telescope side to accept male-threaded optical components.
In total, six rings are included: M42, M48, M54 (male) and F42, F48, F54 (female). These allow the drawer to be configured as M42, M48 or M54 on either side, in male or female orientation. You can even set both sides to male or both to female, depending on your setup requirements.
M42 / M48 / M54 Male Thread Rings
M-type rings provide a male thread for connecting to cameras or camera-side accessories.
F42 / F48 / F54 Female Thread Rings
F-type rings provide a female thread for connecting to telescopes or telescope-side accessories.
Five of the six rings (all except F-54) attach directly to the drawer frame using standard threading—no tools required. F-54 is a drop-in ring without threads: simply place it into the drawer frame when an M54 female connection is needed.
