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Starizona Threaded Focuser Adapter
Starizona Threaded Focuser Adapter
Starizona Threaded Focuser Adapter
Starizona Threaded Focuser Adapter
Starizona Threaded Focuser Adapter
Starizona Threaded Focuser Adapter

Starizona Threaded Focuser Adapter

by Starizona
SKU STZ-TFA-M54M-M42M
$49.95 USD - $79.95 USD
$69.95 USD
$49.95 USD - $79.95 USD
$69.95 USD
Price Match Policy!
  • Solid, threaded connection eliminates tilt and sag
  • Available for dozens of focuser thread standards
  • Choice of M42 or M48 camera-side threads
  • Precision-machined for perfect optical alignment
  • Includes spacers for fine-tuning backfocus
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  • Description
  • FAQ
  • Specifications
  • Warranty

  • Starizona Threaded Focuser Adapter

    The Starizona Threaded Focuser Adapter provides a secure, all-threaded connection between your telescope's focuser and your M42 or M48 imaging train. With dozens of available models, it supports a vast range of focuser threads from M54 up to M102 and even 2.7" Astro-Physics standards, replacing unstable compression rings with a rigid, tilt-free interface.

    Secure Threaded Adaptation from M54 to M102 Focusers

    This adapter is the critical first link in a solid imaging train. By threading directly onto your focuser's drawtube, it eliminates the flexure, sag, and tilt common with slip-fit or compression-ring adapters. The result is a perfectly co-linear optical axis, which is essential for achieving sharp, round stars from edge to edge.

    Starizona offers versions to fit a huge variety of modern and classic focusers, including those from Takahashi (M72), Explore Scientific (M68 and M88), Astro-Physics (2.7"), FeatherTouch (M75), and many others. This ensures you can create a robust mechanical connection regardless of your telescope brand, locking your reducer, flattener, or camera directly to the focuser.

    Standardized M42 and M48 Camera-Side Connections

    On the camera side, you can choose between the two most common imaging standards: M42x0.75 (T-thread) and M48x0.75 (2" filter thread). M42 offers maximum compatibility with legacy accessories and smaller sensors, while M48 provides a wider, unvignetted light path for full-frame and large APS-C sensors.

    • Backfocus Management: These adapters consume a small amount of backfocus. Each adapter includes spacers to help you precisely dial in the correct distance to your sensor.
    • M42 vs. M48 Path Length: Note that the M42 and M48 versions consume different amounts of backfocus, a critical detail to account for when planning your optical train.

  • Why use a Starizona Threaded Focuser Adapter instead of a 2" nosepiece?

    A threaded adapter creates a rigid, secure connection that prevents tilt and sag. A 2" nosepiece held by a thumbscrew or compression ring can easily shift as the telescope slews, throwing off collimation and resulting in elongated stars. For imaging, a fully threaded connection like the Starizona adapter is always the superior choice for maintaining perfect optical alignment.

    Which camera thread should I choose for my Starizona adapter, M42 or M48?

    The choice depends on your camera's sensor size and your other accessories.

    • M42 (T-thread): Best for cameras with smaller sensors (like the ASI533MC) or if your existing spacers and filter wheels are all M42.
    • M48 (2" Filter Thread): Recommended for cameras with APS-C or full-frame sensors (like the ASI2600MC or ASI6200MM) to prevent vignetting, which is the darkening of the corners of your image.

    How do I know which Starizona adapter fits my telescope focuser?

    You need to know the specific thread size and gender (male or female) on your focuser's drawtube. This is often listed in your telescope's manual or on the manufacturer's website. For example, many Takahashi focusers use an M72 female thread, while some Explore Scientific focusers use an M68 female thread. Carefully measure or verify your focuser's thread before ordering.

    Do the Starizona Threaded Focuser Adapters affect my backfocus?

    Yes, all adapters consume some amount of backfocus. The exact amount is different for the M42 and M48 versions of the adapter. Starizona includes spacers with each adapter to give you more flexibility in achieving the precise spacing required by your flattener or reducer.

    I have a Takahashi with an M72 thread and want to connect a full-frame camera. Which Starizona adapter is best?

    For that setup, you would select the Starizona adapter with "M72 x 1mm Female (Takahashi)" threads on the focuser side. Because you are using a full-frame camera, you should choose the M48 version for the camera side to minimize vignetting and ensure your sensor is fully illuminated.

    How does this Starizona adapter help build a rigid imaging train on my Explore Scientific refractor with a 2.5" Hex focuser?

    The 2.5" Hex focuser typically has M68 x 0.75mm female threads. By selecting the corresponding Starizona adapter, you can thread your entire imaging train—reducer, filter wheel, and camera—directly onto the focuser drawtube. This creates a single solid unit, preventing any part of your camera setup from flexing or tilting as the telescope moves across the sky.

  • Available Options M54 x 1mm Male (2-Part) / M42, M54 x 1mm Male (2-Part) / M48, M56 x 1mm Female (Esatto 2") / M48, M58 x 1mm Female / M48, M63 x 1mm Male / M42, M63 x 1mm Male / M48, M65 x 1mm Female / M48, M68 x 1mm Male / M42, M68 x 1mm Male / M48, M68 x 0.75mm Female (Explore Scientific) / M42, M68 x 0.75mm Female (Explore Scientific) / M48, M72 x 1mm Female (Takahashi) / M42, M72 x 1mm Female (Takahashi) / M48, M74 x 1mm Female (Esprit) / M42, M74 x 1mm Female (Esprit) / M48, M74 x 1mm Male / M42, M74 x 1mm Male / M48, M75 x 1mm Male (3" FeatherTouch) / M42, M75 x 1mm Male (3" FeatherTouch) / M48, M81 x 1mm Female (Esatto 2") / M48, M82 x 1mm Female / M42, M82 x 1mm Female / M48, M82 x 1.25mm Male (Exp. Sci. Self-Center, ES-FOCS3) / M48, M84 x 1mm Female (Askar 103/120) / M42, M84 x 1mm Female (Askar 103/120) / M48, M86 x 1mm Female / M42, M86 x 1mm Female / M48, M88 x 1mm Male (Explore Scientific 3") / M42, M88 x 1mm Male (Explore Scientific 3") / M48, M92 x 1mm Female (Askar 140/185) / M42, M92 x 1mm Female (Askar 140/185) / M48, M102 x 1mm Male (iStar/Airy-Disk 140) / M42, M102 x 1mm Male (iStar/Airy-Disk 140) / M48, 2.7" x 24tpi Male (Astro-Physics) / M42, 2.7" x 24tpi Male (Astro-Physics) / M48
  • Starizona Warranty