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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 M54 Extension Tube – 15 mm
Baader Planetarium M54 Extension Tube – 15 mm
Baader Planetarium M54 Extension Tube – 15 mm

Baader Planetarium M54 Extension Tube – 15 mm

by Baader Planetarium
SKU BAA-2958715
$53.00 - $53.00
$53.00
$53.00 - $53.00
$53.00
Price Match Policy!
  • Adds a precise 15 mm of optical path length
  • Standard M54 (M54x0.75) threads for modern imaging trains
  • Machined from metal for rigidity and stability
  • Essential for achieving correct back focus with flatteners and reducers
2 in stock
Qualifies for FREE Shipping in CONUS on orders over $350.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • M54 Extension Tube – 15 mm

    This M54 Extension Tube adds a fixed 15 mm of length to any M54-threaded optical train. This precise 15 mm spacing is essential for matching the required back focus of field flatteners, coma correctors, and focal reducers to your camera sensor's position, ensuring edge-to-edge sharpness in your images.

    Achieve Critical Back Focus with 15mm of M54 Extension

    Modern optical correctors demand precise spacing to function correctly. This 15 mm extension tube serves as a rigid, reliable component for bridging the gap between your corrector and camera, helping you achieve the exact spacing needed for optimal performance. Its fixed length provides a stable, flex-free connection that complex, adjustable adapters can lack.

    • Fixed 15 mm Length: Provides a non-adjustable, solid increase in your optical path length, ensuring consistent and repeatable spacing.
    • M54 Thread Standard: Connects seamlessly with the M54 threads found on a wide range of modern correctors, filter wheels, off-axis guiders, and large-format astronomy cameras.
    • Back Focus Solution: An essential building block for assembling imaging trains that meet the strict spacing tolerances of high-performance optical systems.

  • What is the primary use for the M54 Extension Tube – 15 mm?

    The primary use of the M54 Extension Tube – 15 mm is to add a precise 15 mm of distance within an astrophotography imaging train. This is most often required to achieve the exact back focus distance specified by a focal reducer, field flattener, or coma corrector for a specific camera sensor.

    How do I know if I need a 15 mm M54 extension tube for my setup?

    You need to calculate the total back focus of your current imaging train. Start with the corrector's required back focus (e.g., 55 mm is common), then subtract the back focus of your camera and the thickness of any components in between (like a filter wheel or off-axis guider). If the remaining distance you need to fill is 15 mm, this tube is the correct component.

    Is this M54 Extension Tube threaded on the inside and outside?

    Yes. Standard extension tubes like this one feature male M54 threads on one end and female M54 threads on the other. This allows them to be inserted between two other M54-threaded components, such as a corrector and a camera adapter.

    Can I stack this 15 mm M54 Extension Tube with other extenders?

    Absolutely. You can stack multiple extension tubes to achieve a specific distance. For example, if you need 35 mm of spacing, you could combine this 15 mm tube with a 20 mm tube. Using a single, fixed-length tube is generally preferred for rigidity where possible.

    Will this 15 mm extension tube work with my Celestron EdgeHD telescope and 0.7x reducer?

    It can be part of the solution. The Celestron 0.7x reducer for EdgeHD scopes requires a very specific back focus. Many imagers use M54-threaded components to build a rigid imaging train off this reducer. This 15 mm tube could be the final piece you need to achieve the correct spacing, depending on your camera and other accessories.

    I'm connecting a ZWO camera to an M54 filter wheel. Could this 15 mm M54 tube be useful?

    Yes, this is a common scenario. If your corrector, filter wheel, and camera adapters don't naturally add up to the required back focus distance, this 15 mm tube can be inserted into the M54-threaded train to make up the difference. It's a simple and effective way to ensure your spacing is perfect for sharp stars.