William Optics Longer adjusting adapter for FLAT68III, FLAT7A
- Connects FLAT68III & FLAT7A Flatteners to M48 Imaging Trains
- Provides a Fixed 45mm Optical Length
- Input Thread: M80 x 0.75 Male
- Output Thread: M48 x 0.75 Male
The William Optics WO-AD-M80-45-M48 is a crucial component for achieving perfect back focus, providing a fixed 45mm of optical length between your flattener and camera. It connects the M80 x 0.75 female thread on a FLAT68III or FLAT7A flattener to the standard M48 x 0.75 thread common to most astronomy cameras, filter wheels, and off-axis guiders.
This adapter solves a common spacing problem for imagers using William Optics' high-end flatteners. When your camera's sensor-to-flange distance, combined with other accessories, doesn't add up to the required back focus, this 45mm adapter fills that critical gap with a single, rigid component, minimizing tilt and flexure in your imaging train.
This adapter is designed to provide a precise 45mm of optical spacing. It's used to connect a William Optics FLAT68III or FLAT7A flattener (which has an M80 thread) to an imaging train that uses the standard M48 thread, helping you achieve the correct back focus distance required by the flattener.
You need to calculate the total back focus of your imaging train. Start with the flattener's required back focus distance, then subtract the back focus of your camera and any accessories (filter wheel, off-axis guider). If the remaining distance you need to fill is 45mm, this adapter is the perfect single-piece solution.
Both the M80 x 0.75 (Light-In) and M48 x 0.75 (Light-Out) threads on this adapter are male. It is designed to thread into the female port on the flattener and connect to a female M48 thread on your next accessory.
No, it is not. The adapter provides a fixed, rigid optical length of 45mm. The term "adjusting adapter" in the title refers to its role in helping you *adjust* your overall back focus to the correct distance, not that the adapter itself is variable.
Physically, it might thread on if another flattener uses an M80 x 0.75 female port. However, it is mechanically and optically designed specifically for the William Optics FLAT68III and FLAT7A to achieve their intended back focus. Using it with other flatteners is not recommended as it will likely result in incorrect spacing.
Using a single, solid 45mm adapter like the WO-AD-M80-45-M48 is mechanically superior to stacking multiple smaller spacers. A single component minimizes the potential for tilt, flexure, and light leaks in the imaging train, leading to sharper stars across the entire field of view.
| Input Thread (Light-In Side) | M80 x 0.75 |
| Output Thread (Light-Out Side) | M48 x 0.75 |
| Optical Length | 45 mm |
William Optics M80 to M48 Adapter (45mm)
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