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William Optics Longer adjusting adapter for FLAT68III, FLAT7A

William Optics Longer adjusting adapter for FLAT68III, FLAT7A

by William Optics
SKU WO-AD-M80-45-M48
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CA$80.00
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  • Connects FLAT68III & FLAT7A Flatteners to M48 Imaging Trains
  • Provides a Fixed 45mm Optical Length
  • Input Thread: M80 x 0.75
  • Output Thread: M48 x 0.75
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • William Optics Longer Adjusting Adapter for FLAT68III, FLAT7A

    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 thread of a FLAT68III or FLAT7A flattener to the standard M48 x 0.75 thread common to most astronomy cameras, filter wheels, and off-axis guiders.

    Precision 45mm Extension for FLAT68III & FLAT7A

    This adapter is a longer replacement for the FLAT68III's original, shorter adjusting adapter. William Optics' Fluorostar 91 manual shows the swap as an optional step when using the FLAT68III on the FLT91.

    • M80 x 0.75 Input: Threads directly and securely onto the William Optics FLAT68III and FLAT7A field flatteners.
    • M48 x 0.75 Output: The standard 2-inch filter thread ensures broad compatibility with the vast majority of dedicated astronomy cameras and imaging accessories.
    • Fixed 45mm Length: Provides a non-adjustable, mechanically stable 45mm of spacing, essential for maintaining a flat field from corner to corner.

  • What is the primary use for the WO-AD-M80-45-M48 adapter?

    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.

    How do I know if I need this 45mm adapter for my FLAT68III and imaging setup?

    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). It is not an add-on spacer: it replaces the original, shorter adjusting adapter on the FLAT68III, which William Optics' FLT91 manual describes as an optional step for the FLT91.

    Is the optical length of the WO-AD-M80-45-M48 adapter adjustable?

    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.

    Can I use the WO-AD-M80-45-M48 with a flattener other than the FLAT68III or FLAT7A?

    Physically, it might thread on if another flattener uses an M80 x 0.75 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.

    Why use a single 45mm adapter instead of stacking smaller spacers?

    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
    Telescope-Side Connection M80x0.75
    Camera-Side Connection M48x0.75

    • William Optics M80 to M48 Adapter (45mm)

      × 1

  • William Optics 2-Year Warranty