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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.
PrimaLuceLab Adapter from M81 to M72 with Stop Ring for ESATTO 3"

PrimaLuceLab Adapter from M81 to M72 with Stop Ring for ESATTO 3"

by PrimaLuceLab
SKU PLL-PL3600272
$95.00 - $95.00
$95.00
$95.00 - $95.00
$95.00
Price Match Policy!
  • Adapts M81 male threads to M72 female threads
  • Designed for PrimaLuceLab ESATTO 3" focusers and ARCO 3" rotators
  • Adds a minimal 4mm of total optical length
  • Includes a stop ring for precise, lockable camera rotation
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • PrimaLuceLab Adapter from M81 to M72 with Stop Ring for ESATTO 3"

    The PrimaLuceLab Adapter seamlessly connects accessories with an M72 female thread to the large M81 male thread on your ESATTO 3" robotic focuser or ARCO 3" camera rotator. With the included stop ring, the complete assembly adds only 4mm of optical length, preserving critical backfocus for complex imaging trains.

    M81 to M72 Connection for ESATTO 3" and ARCO 3"

    This adapter provides the essential mechanical link between PrimaLuceLab's large-format focusers and the wide ecosystem of imaging accessories that use the M72 thread standard. It allows you to securely attach field flatteners, reducers, or camera-specific adapters directly to the ESATTO 3" drawtube for a rigid, flexure-free connection.

    Precise Framing with a 4mm Optical Path

    More than a simple thread converter, this adapter includes a dedicated stop ring for complete rotational control. You can thread your camera on, rotate it to the perfect angle for your target, and then lock it in place with the stop ring, ensuring your composition remains fixed throughout the imaging session. The entire assembly is engineered for a minimal profile, consuming just 4mm of backfocus (1.5mm for the adapter and 2.5mm for the stop ring).

  • What is the primary function of the PrimaLuceLab M81 to M72 adapter?

    This adapter's primary function is to connect any camera or accessory with a female M72x1 thread to the male M81x1 thread found on the drawtube of the PrimaLuceLab ESATTO 3" focuser and ARCO 3" rotator.

    How does the stop ring on this M81 to M72 adapter improve imaging?

    The stop ring allows you to precisely set and lock the rotational angle of your imaging camera. After threading on your camera, you can adjust its orientation to perfectly frame your target, such as fitting a long galaxy into the sensor's diagonal, and then tighten the stop ring to prevent any rotation during an exposure.

    What is the total optical length of the PrimaLuceLab M81 to M72 adapter?

    The total optical length is 4mm. This is comprised of two parts: the main adapter body, which is 1.5mm thick, and the stop ring, which is 2.5mm thick.

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

    While it is designed and optimized for the PrimaLuceLab ESATTO 3" and ARCO 3", it will technically thread onto any male M81x1 port. However, correct seating and performance are only guaranteed within the PrimaLuceLab ecosystem.

    I need to connect my camera with an M72 thread to an ESATTO 3" on my Ritchey-Chrétien telescope. Is this the right part?

    Yes, this is the exact adapter for your application. It provides a secure M81-to-M72 connection and its minimal 4mm optical length helps preserve the critical backfocus required by most Ritchey-Chrétien optical designs.

    How does this M81 to M72 adapter help when imaging a large target like the Andromeda Galaxy (M31)?

    When imaging a large, elongated object like the Andromeda Galaxy (M31), the stop ring is crucial. It allows you to rotate your camera sensor to align with the galaxy's longest axis, ensuring you capture the full extent of the object within a single frame for optimal composition.

  • Male Thread M81x1
    Female Thread M72x1
    Compatibility PrimaLuceLab ESATTO 3", PrimaLuceLab ARCO 3"
    Total Optical Length 4mm
    Adapter Optical Length 1.5mm
    Stop Ring Optical Length 2.5mm
  • PrimaLuceLab 1-Year Warranty