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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
Player One M48F-M42M Adapter - 17.5mm
Player One M48F-M42M Adapter - 17.5mm

Player One M48F-M42M Adapter - 17.5mm

by Player One
SKU POA-M48F-M42M-17.5
$24.00 - $24.00
$24.00
$24.00 - $24.00
$24.00
Price Match Policy!
  • Adds a precise 17.5mm of optical path length
  • Converts female M48x0.75 threads to male M42x0.75 T-threads
  • Connects M48 accessories like flatteners to M42 cameras and T-rings
  • Machined from aluminum with a non-reflective black anodized finish
1 in stock
Qualifies for FREE Shipping in CONUS on orders over $350.
  • Description
  • FAQ
  • Specifications
  • In the Box
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  • Player One M48F-M42M Adapter - 17.5mm

    Achieving correct back focus between M48-threaded flatteners and M42-threaded cameras requires precise spacing, and the Player One M48F-M42M adapter adds exactly 17.5mm of optical length to bridge this common gap. This single, rigid component simplifies your imaging train by both converting thread standards and extending the optical path, eliminating the need to stack multiple, less stable adapters.

    Achieving 17.5mm Back Focus with M48 to M42 Conversion

    In astrophotography, every millimeter of spacing counts. This adapter is purpose-built to provide a fixed 17.5mm extension, a common requirement for achieving the critical 55mm back focus distance when using various cameras and filter wheels. Its dual-function design solves two problems at once.

    The adapter features a female M48x0.75 (2-inch filter) thread on the telescope side, allowing it to connect directly to most field flatteners, reducers, and off-axis guiders. The camera side has a male M42x0.75 T-thread, the universal standard for connecting to DSLR T-rings and dedicated astronomy cameras.

    • Precise Spacing: Adds exactly 17.5mm to your back focus calculation, a non-standard length that can be difficult to achieve with other spacers.
    • Secure Connection: Machined as a single piece, it prevents flexure and tilt that can occur when stacking multiple smaller adapters.
    • Standardized Threads: Uses the industry-standard M48 and M42 threads with a 0.75mm pitch for broad compatibility across brands.
    • Internal Baffling: A matte black interior finish minimizes internal reflections to maintain image contrast.

  • What is the primary use for the Player One M48F-M42M 17.5mm adapter?

    This adapter is designed to add exactly 17.5mm of spacing in an astrophotography imaging train while simultaneously adapting the larger M48 (2-inch filter) thread to the smaller M42 T-thread. It's a specialized component for hitting a precise back focus target.

    I have a flattener with an M48 thread that requires 55mm of back focus, and my camera has an M42 thread and 12.5mm of flange distance. Will this Player One 17.5mm adapter work?

    No. In your scenario, you need 55mm - 12.5mm = 42.5mm of total spacing. The 17.5mm adapter by itself is not long enough. This adapter is for imaging trains where 17.5mm is the specific gap required to reach the target back focus.

    Can I use the Player One 17.5mm adapter to connect my ZWO filter wheel (M48) to my Canon DSLR with an M42 T-ring for imaging the Andromeda Galaxy (M31)?

    Yes, this is a very common application. This adapter provides the physical thread conversion between the M48 filter wheel and the M42 T-ring. You must ensure that the total optical path length of your filter wheel, T-ring, and this 17.5mm adapter adds up to the correct back focus distance specified by your telescope's flattener or reducer.

    What do "M48F" and "M42M" mean on the Player One adapter?

    M48F stands for a female M48x0.75 thread, which receives a male M48 accessory. M42M stands for a male M42x0.75 thread, which threads into a female M42 T-ring or camera body.

    Is the thread pitch on this Player One adapter the standard 0.75mm?

    Yes, both the M48 and M42 threads use the standard astronomical pitch of 0.75mm. This ensures full compatibility with equipment from nearly all major astrophotography brands.

    Does the Player One M48F-M42M adapter have internal threads for filters?

    No. This component is a dedicated thread adapter and spacer. It does not have internal threads to mount a filter. Filters must be placed elsewhere in the optical train, such as in a filter drawer or filter wheel.

  • Product Type Thread Adapter / Extension Tube
    Optical Length 17.5mm
    Telescope Side Thread M48x0.75 Female
    Camera Side Thread M42x0.75 Male
    Material Aluminum
    Finish Black Anodized

    • Player One M48F-M42M Adapter - 17.5mm

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