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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.
PrimaLuceLab 9mm T2 Extension

PrimaLuceLab 9mm T2 Extension

by PrimaLuceLab
SKU PLL-PL3304209
$24.00 - $24.00
$24.00
$24.00 - $24.00
$24.00
Price Match Policy!
  • Provides 9mm of fixed spacing
  • T2 threads (male on one side, female on the other)
  • Black anodized metal construction
  • Knurled exterior for a secure grip
  • Stackable with other T2 extensions and spacers
1 in stock
Qualifies for FREE Shipping in CONUS on orders over $350.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • PrimaLuceLab 9mm T2 Extension

    The PrimaLuceLab 9mm T2 Extension adds a fixed 9mm of spacing to your imaging train, essential for setting the precise backfocus required by field flatteners and focal reducers. By combining this 9mm extension with optional 1mm and 0.5mm spacers, you can create custom lengths in precise 0.5mm increments to perfectly match your camera and corrector's optical prescription.

    Achieve 9mm of Precise Backfocus with T2 Threads

    This extension is engineered to solve a critical imaging problem: achieving the exact distance from your corrector lens to your camera sensor. Made from black-anodized metal to prevent internal reflections, this rigid 9mm spacer ensures your components remain perfectly collinear. An external knurled grip provides excellent leverage, making it easy to tighten or remove the extension, even when wearing gloves on a cold night.

    While a single 9mm extension is fixed, its primary function is as a component in a modular system. You can screw multiple extensions together or insert thin T2 spacers between them, allowing you to build the exact spacing your optical train demands without introducing any flexure.

  • What is the PrimaLuceLab 9mm T2 Extension used for?

    It is primarily used to add a precise 9mm of distance within an astrophotography imaging train. This is crucial for achieving the correct backfocus distance specified by a focal reducer, field flattener, or coma corrector to ensure sharp stars across the entire field of view.

    Can I stack multiple PrimaLuceLab 9mm T2 extensions?

    Yes. These extensions are designed to be screwed together to create longer spacing. For example, two 9mm extensions can be combined to create an 18mm extension. For finer adjustments, you can also add PrimaLuceLab's 0.5mm and 1mm T2 spacers.

    How would I get a spacing of 10.5mm with this PrimaLuceLab T2 extension?

    To achieve a custom spacing like 10.5mm, you would combine this 9mm T2 Extension with other available spacers. The combination would be:

    • One 9mm T2 Extension
    • One 1mm T2 Spacer
    • One 0.5mm T2 Spacer

    This modularity allows you to build virtually any backfocus distance you need in 0.5mm steps.

    My Celestron EdgeHD 8" with its 0.7x reducer needs 105mm of backfocus. How does this 9mm extension help?

    The 105mm backfocus for the EdgeHD 8" reducer is a common requirement. The PrimaLuceLab 9mm T2 Extension is one of the building blocks you would use to reach that total distance. You would measure the existing distance provided by your camera, off-axis guider, and filter wheel, and then use a combination of extensions, including this 9mm piece, to make up the remaining difference to hit exactly 105mm.

    What are the threads on the PrimaLuceLab 9mm T2 Extension?

    The extension uses the standard T2 thread, which is also known as M42x0.75. It features male T2 threads on one side and female T2 threads on the other, allowing it to be inserted between any two T2-threaded components like a camera nosepiece and a corrector.

    Why does the PrimaLuceLab 9mm T2 Extension have a knurled grip?

    The knurled (grooved) texture on the outside of the extension provides a secure gripping surface. This makes it much easier to screw and unscrew the extension by hand, especially in cold or dark conditions where getting a firm grip on a smooth metal surface can be difficult.

  • Extension Length 9mm
    Threads T2 (M42x0.75) Male and Female
    Material Metal
    Finish Black Anodized with Knurled Grip

    • 9mm T2 Extension

      × 1

  • PrimaLuceLab 1-Year Warranty