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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.
Baader Planetarium Adapter M55a to M68i
Baader Planetarium Adapter M55a to M68i
Baader Planetarium Adapter M55a to M68i
Baader Planetarium Adapter M55a to M68i
Baader Planetarium Adapter M55a to M68i
Baader Planetarium Adapter M55a to M68i
Baader Planetarium Adapter M55a to M68i
Baader Planetarium Adapter M55a to M68i
Baader Planetarium Adapter M55a to M68i

Baader Planetarium Adapter M55a to M68i

by Baader Planetarium
SKU BAA-2458234
$85.00 - $85.00
$85.00
$85.00 - $85.00
$85.00
Price Match Policy!
  • Adapts M55 External (M55a) Threads
  • Provides a Secure M68 Internal (M68i) Thread
  • Enables Connection to the Baader M68 System
  • Designed for Specific Baader Mirrors and Diagonals
  • Prevents Vignetting with Large Format Sensors
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Adapter M55a to M68i

    The Baader Planetarium Adapter M55a to M68i is a specialized expansion ring designed to integrate components into the larger, more robust Baader M68 optical system. It directly converts an M55 external thread into a secure M68 internal thread, opening up compatibility with a wide range of professional-grade accessories for serious imaging.

    Convert M55 Threads to the M68 System for Secure Imaging

    This adapter serves a critical function: bridging the gap between components using the M55 thread and the versatile Baader M68 system. By providing a secure M68 internal thread, you can create a rigid, wide-aperture connection for your imaging train. This is essential for attaching M68 accessories like off-axis guiders, filter wheels, or spacers without introducing flexure or vignetting, especially when using cameras with large sensors.

    Installation Note: Face Spanner #2450062 Recommended

    Proper installation of this adapter on compatible Baader mirrors or diagonals requires a specific procedure. You must first unthread and remove the standard 2" barrel and the M55 / 2" UNC threaded ring from the component's housing. Baader Planetarium recommends using their Face Spanner (#2450062) to safely perform this task before threading on the M55a to M68i adapter.

  • What is the primary use for the Baader M55a to M68i Adapter?

    The Baader M55a to M68i Adapter is used to connect accessories with an M55 external thread to the Baader M68 system, providing a larger, more secure M68 internal thread. This is ideal for building rigid, wide-aperture imaging trains that minimize vignetting and prevent flexure.

    Do I need a special tool to install the M55a to M68i Adapter?

    Yes, proper installation often requires a specific tool. To fit this adapter to a compatible Baader mirror or diagonal, you must first remove the existing 2" barrel and M55 retaining ring. Baader strongly recommends using their Face Spanner (#2450062) for this task to avoid damage.

    Will this adapter help reduce vignetting in my imaging setup with a Baader diagonal?

    Yes. By converting the connection to the larger M68 standard, this adapter provides a wider, un-obstructed light path compared to a standard 2" nosepiece or a smaller M55 thread. This is a key benefit for minimizing vignetting, especially when imaging with large-format APS-C or full-frame camera sensors.

    How does the M55a to M68i Adapter help when imaging galaxies like Andromeda (M31) with a large sensor camera?

    When imaging large targets like the Andromeda Galaxy (M31) with a full-frame or APS-C sensor, maintaining an unvignetted field is critical. This adapter allows you to build a complete M68 threaded imaging train from your diagonal to the camera, ensuring the light cone is not clipped by smaller adapters, resulting in more evenly illuminated images across the entire frame.

    What kind of accessories can I attach after installing the M55a to M68i Adapter?

    Once installed, your component will have a female M68 thread, allowing you to attach any accessory from the Baader M68 system. This includes the M68 Off-Axis Guider, M68 filter changers, or various M68 extension tubes needed to achieve precise back focus distances.

    Is this adapter the same as a standard step-up ring?

    It is more specialized. While it functions as a step-up ring (M55 to M68), it is specifically engineered to replace the 2" barrel assembly on certain Baader components. This makes it an integrated part of the optical system rather than a simple, generic add-on adapter.

  • Baader Planetarium Warranty