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Closed October 10–12 for Thanksgiving weekend
Closed October 10–12 for Thanksgiving weekend
ZWO M48-M42 Adapter

ZWO M48-M42 Adapter

by ZWO
SKU ZWO-M48-M42
CA$17.00 - CA$17.00
CA$17.00
CA$17.00 - CA$17.00
CA$17.00
Price Match Policy!
  • Converts female M48x0.75 threads to female M42x0.75 T-threads
  • Adds 0mm of optical path length to the imaging train
  • Standard accessory with most ZWO cooled cameras
  • Durable black anodized aluminum construction
10 in stock
Qualifies for FREE Shipping in Canada on orders over $500.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • ZWO M48 to M42 Adapter

    The ZWO M48 to M42 Adapter is the essential component for connecting accessories with different thread standards, converting the wider M48 (2-inch filter) thread to the universal M42 T-thread. This simple ring doesn't add any back focus, making it a compact solution for integrating filter wheels, flatteners, and cameras into a single, secure optical train.

    A Zero-Length Solution for Thread Incompatibility

    This adapter solves one of the most common connection problems in astrophotography. It threads into a female M48 port on an accessory such as a filter drawer or field flattener and presents a female M42 T-thread for a male M42 component such as an off-axis guider or T-ring. The adapter has a male M48 thread on the outside and a female M42 thread on the inside, so it sits within the M48 thread and occupies 0mm of optical distance.

    Designed for ZWO Pro Camera Systems

    While universally useful, this M48-M42 adapter is the same unit included with most ZWO cooled cameras. It's specifically designed to work with other ZWO accessories like the 16.5mm extender or an Off-Axis Guider (OAG). When used in these specific configurations, it provides the correct thread type without altering the designed total back focus of the system, ensuring you can reach the required 55 mm spacing without complex calculations.

  • What is the primary use for the ZWO M48-M42 Adapter?

    Its primary function is to convert the larger M48x0.75 female thread, commonly found on 2-inch filter holders and field flatteners, into the smaller M42x0.75 female T-thread used by most astronomy cameras, T-rings, and off-axis guiders. This allows you to connect components that would otherwise be incompatible.

    How much back focus does the ZWO M48-M42 Adapter use?

    The adapter itself has an optical path length of 0mm.

    Is this the same adapter that comes with ZWO cameras?

    Yes, this is the same stock M48-M42 adapter ring that is included with most ZWO cooled cameras. It is offered here as a replacement part or for users who need to adapt other non-ZWO hardware.

    Can I use the ZWO M48-M42 Adapter to connect a 2" filter wheel to my camera's T-ring?

    Yes, this is a perfect application. If your 2" filter wheel or drawer has a female M48 thread and your T-ring has a male M42 thread, this adapter threads into the M48 port and accepts the M42 T-ring, consuming no additional back focus.

    Will this ZWO adapter cause vignetting on my full-frame camera?

    Because this adapter steps down from the larger M48 format to the smaller M42 T-thread, it can introduce vignetting on full-frame (24x36mm) sensors, especially in fast optical systems (f/5 or lower). The M42 thread has a smaller clear aperture than M48, which can clip the light cone before it reaches the corners of a large sensor.

    What are the threads on the ZWO M48-M42 Adapter?

    The adapter has a male M48x0.75 thread on the outside and a female M42x0.75 T-thread on the inside.

  • SKU ZWO-M48-M42
    Thread Conversion M48x0.75 (Male) to M42x0.75 (Female)
    Optical Length 0 mm
    Warranty 2 Years

    • ZWO M48 to M42 Adapter Ring

      × 1

  • ZWO 2-Year Limited Warranty