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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.
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 M48 Extension Tube 30mm / 2" Nosepiece with Safety Kerfs

Baader M48 Extension Tube 30mm / 2" Nosepiece with Safety Kerfs

by Baader Planetarium
SKU BAA-2958630
$44.00 - $44.00
$44.00
$44.00 - $44.00
$44.00
Price Match Policy!
  • Adds exactly 30mm of optical path length
  • Functions as a standard 2" nosepiece
  • Connects M48x0.75 female threads to a 2" focuser
  • Features Baader's proprietary Safety Kerfs to prevent slippage
  • Engineered with a 3mm thread depth for modern cameras
1 in stock
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Baader M48 Extension Tube 30mm / 2" Nosepiece with Safety Kerfs

    The Baader M48 Extension Tube provides a fixed 30mm of optical path length while simultaneously acting as a 2" nosepiece for direct insertion into any standard 2-inch focuser or visual back. This dual-purpose adapter uses M48x0.75 threads and incorporates Baader's unique Safety Kerfs, offering a secure, non-slip connection for your imaging train. Its design includes a modern 3mm thread depth, making it fully compatible with the latest generation of astronomy cameras that feature minimal body depth.

    Dual-Purpose Design: 30mm Extension & 2" Nosepiece

    This component solves two common imaging problems in one. As an extension tube, it supplies a precise 30mm of spacing, critical for achieving the correct distance between a field flattener or reducer and your camera sensor. As a nosepiece, it allows any M48-threaded accessory, like a filter drawer or off-axis guider, to be securely mounted in a 2" focuser drawtube.

    Secure Mounting: Safety Kerfs & 3mm Thread Depth

    Standard nosepieces often use a simple undercut groove that can snag on focuser compression rings, or a smooth barrel that can slip and cause your camera to fall. Baader's Safety Kerfs are a series of machined grooves that provide multiple points of contact for a setscrew or compression ring, ensuring your equipment stays locked in place without risk of binding or slipping. The shallow 3mm thread depth is a deliberate choice, accommodating modern, low-profile cameras that cannot accept older, deeper T-2 standard threads.

  • What is the primary use for the Baader M48 30mm Extension Tube?

    This adapter serves two main functions. First, it adds a precise 30mm of length to an M48-threaded imaging train to achieve correct back focus. Second, it allows you to insert that entire M48 accessory stack directly into a standard 2" focuser, acting as a secure nosepiece.

    How do the "Safety Kerfs" on this Baader M48 nosepiece work?

    The Safety Kerfs are a series of shallow, rounded grooves machined into the barrel. Unlike a single deep undercut that can snag, these kerfs provide a secure grip for your focuser's compression ring or setscrew. If the focuser loosens slightly, the screw will catch in a kerf instead of allowing the entire nosepiece to slip out, preventing catastrophic drops of your camera and accessories.

    Will this Baader M48 extension tube work with non-Baader M48 accessories?

    Yes. The M48x0.75 thread pitch is an industry standard for 2" filters and many imaging correctors. This Baader extension tube will connect to any accessory that uses a standard male M48 thread.

    Why does this Baader M48 nosepiece have a 3mm thread depth?

    The 3mm thread depth is a modern standard adopted by Baader to ensure compatibility with the newest generation of astronomy cameras. Many modern cameras have very thin bodies with minimal back focus, and cannot physically accommodate older accessories with deeper 5mm threads. This shallow depth ensures a secure connection without bottoming out.

    Can I use the Baader M48 30mm Extension Tube to achieve focus with my ZWO ASI camera on a Newtonian?

    Yes, this is a common application. If your coma corrector requires additional spacing to meet the 55mm back focus standard of many ZWO cameras (like the ASI2600MC Pro or ASI533MC Pro), this 30mm extension can provide a significant portion of that required distance. You would then use smaller, fine-tuning spacer rings to dial in the final distance perfectly.

    Can I stack this Baader M48 30mm extension tube with other spacers?

    Yes, but with a caution. You can thread other male M48 spacers into this extension tube. However, be mindful of rigidity. Stacking too many extensions can introduce flexure into the imaging train, especially with heavier cameras. For longer distances, it is often better to use a single extension tube of the correct length if possible.

  • Net weight (kg) 0.04
    Compatible Brands Baader Planetarium
    Clamping System no clamp
    Inner Diameter / Clear Aperture (mm) 45 mm
    Outer Diameter 53 mm
    Type of Adapter Nosepiece, Extension
    Optical length (mm) 30 (or 4)
    Usage Adjusting the distances of accessories with M48 thread, M48 / 2" nosepiece
    Outer Connection (eyepiece/-camera-sided) M48
    Inner Connection (lens sided) ø 2" (50.8mm), M48
    Adapters Family M48 System
  • Baader Planetarium Warranty