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SBIG 2" Nosepiece - STL Threads (2.156" x 24)
SBIG 2" Nosepiece - STL Threads (2.156" x 24)

SBIG 2" Nosepiece - STL Threads (2.156" x 24)

by SBIG
SKU DL-40-12121-00
$109.00 USD - $109.00 USD
$109.00 USD
$109.00 USD - $109.00 USD
$109.00 USD
Price Match Policy!
  • Connects SBIG accessories to any 2" telescope focuser
  • Camera Connection: 2.156" x 24 TPI Male STL Thread
  • Telescope Connection: 2" Male Barrel
  • Provides a larger clear aperture to reduce vignetting
  • Screws into the SBIG STL Thread Adapter Plate (40-12053-00)
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • SBIG 2" Nosepiece - STL Threads (2.156" x 24)

    The SBIG 2" Nosepiece with STL threads provides a secure, wide-aperture connection between your SBIG imaging train and any standard 2-inch focuser, and screws into the STL Thread Adapter Plate (40-12053-00) used with the AFW-8-36R filter wheel and StarChaser SC-4C. Its camera-side male STL thread measures 2.156 inches with 24 TPI, larger than a T-thread, and this STL combination is recommended when using off-axis guide cameras for its larger unvignetted field.

    Connect Your SBIG System to Any 2" Focuser

    This adapter provides the essential physical interface between your SBIG accessory stack and your telescope. The male 2-inch barrel slides directly into any standard 2" focuser or visual back, allowing for a simple and secure attachment.

    The 2.156" Advantage for Off-Axis Guiding

    The key feature of this nosepiece is its large 2.156-inch STL thread. This larger diameter creates a wider, unvignetted light path compared to adapters using smaller T-threads. The STL thread combination is recommended when using off-axis guide cameras such as the StarChaser SC-4C, as it provides a larger unvignetted field.

    STL vs. T-Thread: Why the 2.156" Bore Matters

    SBIG offers 2-inch nosepieces in two thread types, and choosing the correct one is determined by your specific imaging train. While the T-thread (M42) version connects directly to some camera bodies, this STL-thread version is designed for a different purpose.

    • STL Thread (2.156"): This version threads into the SBIG STL Thread Adapter Plate (40-12053-00), which is used with the AFW-8-36R filter wheel and StarChaser SC-4C. This combination is recommended with off-axis guide cameras for its larger unvignetted field.
    • T-Thread (M42): A smaller-aperture option that screws directly into the camera body of Aluma CCD and STC series cameras for simple setups without a filter wheel or OAG.

  • What is the SBIG 2" Nosepiece with STL threads used for?

    This adapter connects specific SBIG accessories, such as a filter wheel or off-axis guider, to a standard 2-inch telescope focuser. Its primary function is to provide a secure mechanical connection with a large clear aperture to prevent vignetting.

    Which SBIG accessories is this 2.156" x 24 STL nosepiece used with?

    This nosepiece screws into the STL Thread Adapter Plate (40-12053-00). This plate is used with accessories including:

    • AFW-8-36R filter wheel
    • StarChaser SC-4C off-axis guider
    • Legacy models like the FW8-8300, OAG-8300, and others that use the STL adapter plate.

    Do I need another adapter to use this SBIG STL nosepiece?

    Yes. This nosepiece does not thread directly into a camera. It is designed to thread into the SBIG STL Thread Adapter Plate (40-12053-00), which then attaches to your filter wheel or other accessory.

    Why should I choose this STL nosepiece for my SBIG StarChaser SC-4C?

    The StarChaser SC-4C mounts with the STL Thread Adapter Plate, which takes this nosepiece. The STL thread combination is recommended when using off-axis guide cameras, as it provides a larger unvignetted field.

    Will this SBIG 2" nosepiece work with my Schmidt-Cassegrain telescope's 2" visual back?

    Yes. The telescope side of this adapter is a standard male 2-inch barrel. It will slide into and secure in any 2-inch accessory holder, including the visual backs found on most Schmidt-Cassegrain telescopes, refractors, and Newtonians.

    How does the 2.156" thread on the SBIG nosepiece prevent vignetting?

    Vignetting occurs when an opening in the optical path is too small and physically blocks part of the light cone. The 2.156-inch thread (about 54.8 mm) is larger than a 42 mm T-thread, and this STL combination is recommended with off-axis guide cameras because it provides a larger unvignetted field.

  • Telescope-side connection 2in barrel male
    Camera-side connection STL thread 2.156in x 24 tpi male
    Warranty 1 year

    • 2in nosepiece adapter with cap (40-12121-00)

      × 1

  • Diffraction Limited 1-Year Accessory Warranty