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PrimaLuceLab Adapter from M81 to T2 with Stop Ring for ESATTO 3"

PrimaLuceLab Adapter from M81 to T2 with Stop Ring for ESATTO 3"

by PrimaLuceLab
SKU PLL-PL3600282
CA$133.00 - CA$133.00
CA$133.00
CA$133.00 - CA$133.00
CA$133.00
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  • Adapts the M81 male thread of ESATTO 3" or ARCO 3" systems to a standard T2 (M42x0.75) female thread
  • Enables direct connection of T2-threaded cameras, filter wheels, and off-axis guiders
  • Features an independent stop ring for precise rotational adjustment of your imaging train
  • Provides a secure, rigid connection for maintaining optical alignment
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • PrimaLuceLab Adapter from M81 to T2 with Stop Ring for ESATTO 3"

    This PrimaLuceLab adapter provides the essential connection between the large M81 thread of the ESATTO 3" robotic focuser or ARCO 3" rotator and the universally common T2 (M42x0.75) thread used by most dedicated astronomy cameras and accessories. It's a fundamental component for integrating your existing T2-based imaging train with PrimaLuceLab's large-format focusers, ensuring a solid and direct-threaded connection.

    M81 to T2 Thread Conversion for ESATTO 3" & ARCO 3"

    The primary function of this adapter is to bridge the gap between two critical standards. It allows you to securely attach your T2-threaded camera, filter wheel, or off-axis guider directly to the robust M81 drawtube of your ESATTO 3" or ARCO 3", bypassing the potential flexure of compression fittings. This direct-thread approach is critical for maintaining the strict optical alignment required for high-resolution imaging, especially with heavy equipment trains.

    Precise Framing Control with the T2 Stop Ring

    Beyond simple adaptation, this unit includes a crucial stop ring for rotational control. Once your camera is threaded on, you can slightly loosen the stop ring, rotate the entire imaging train to achieve perfect framing on your target, and then lock it down without losing focus or alignment. This feature is indispensable for composing images of elongated objects like the Andromeda Galaxy (M31) or the Pleiades cluster (M45) to match your sensor's orientation.

  • What is the primary purpose of the PrimaLuceLab M81 to T2 adapter?

    Its main purpose is to allow you to connect any astrophotography accessory with a standard T2 (M42x0.75) female thread to the large M81 male thread found on the drawtube of the PrimaLuceLab ESATTO 3" focuser and ARCO 3" rotator. This makes the focuser compatible with a vast ecosystem of cameras, filter wheels, and guiders.

    How does the stop ring on this adapter help when imaging a target like the Orion Nebula (M42)?

    The stop ring gives you precise rotational control over your camera. For a large target like the Orion Nebula (M42), you can orient your camera sensor to capture the full extent of the nebula and the Running Man Nebula in a single frame. You simply thread the adapter on, loosen the stop ring, rotate your camera to the desired angle, and then tighten the ring to lock the position securely.

    Is this PrimaLuceLab adapter compatible with focusers other than the ESATTO 3"?

    This adapter is specifically designed for the M81x1 thread of the PrimaLuceLab ESATTO 3" focuser and ARCO 3" rotator. While it might physically thread onto other focusers with an M81 thread, correct spacing and compatibility are only guaranteed with the intended PrimaLuceLab products.

    Will using the M81 to T2 adapter cause vignetting with my full-frame camera?

    Yes, this is a potential trade-off. The T2 thread has a smaller clear aperture than the M81 thread of the ESATTO 3" focuser. While it is perfect for cameras with smaller sensors (like APS-C or Four Thirds), stepping down to the T2 format will likely cause some vignetting on the corners of a full-frame (24x36mm) sensor. For full-frame imaging, you should consider using M48 or larger adapters.

    Does this adapter add significant back focus to my imaging train?

    This adapter is designed to be as thin as possible to consume minimal back focus. While it does add a small amount of optical path length, it is engineered to allow you to reach focus with most standard T2-based camera and accessory combinations.

    Can I use this adapter with both the ESATTO 3" focuser and the ARCO 3" rotator?

    Yes. Both the ESATTO 3" focuser and the ARCO 3" rotator feature the same M81x1 female thread on their drawtubes, making this adapter fully compatible with either device.

  • PrimaLuceLab 1-Year Warranty