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PrimaLuceLab 7mm T2 Extension

PrimaLuceLab 7mm T2 Extension

by PrimaLuceLab
SKU PLL-PL3304207
CA$27.00 - CA$27.00
CA$27.00
CA$27.00 - CA$27.00
CA$27.00
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  • Provides 7mm of fixed optical spacing
  • Standard T2 (M42x0.75) male and female threads
  • Knurled exterior for a secure grip, even with gloves
  • Black anodized interior and exterior to prevent reflections
  • All-metal construction for rigidity
1 in stock
Qualifies for FREE Shipping in Canada on orders over $500.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • PrimaLuceLab 7mm T2 Extension

    The PrimaLuceLab 7mm T2 Extension provides a fixed 7mm of spacing for precisely setting the backfocus in your imaging train. This all-metal adapter features male and female T2 threads, allowing you to place exactly 7mm of distance between your corrector, camera, or other T2-threaded accessories.

    Achieving 7mm of Critical Backfocus

    Correct backfocus is non-negotiable for achieving sharp stars from edge to edge, and this extension provides a solid 7mm distance to help you hit that target. It can be screwed together with other T2 extensions or combined with fine-tuning spacers, allowing you to build up a custom spacing solution in precise increments.

    Knurled Grip and Anti-Reflection Anodizing

    The extension is machined from metal and features a knurled exterior, providing a secure grip for easy tightening or removal, even with gloves on. Both the interior and exterior surfaces are black anodized to absorb stray light and prevent internal reflections from degrading your image contrast.

  • How do I use the PrimaLuceLab 7mm T2 Extension to reach the 55mm backfocus on my field flattener?

    This 7mm extension is one component you would use to build up the required 55mm distance. You would combine it with your camera's native T-ring depth (e.g., 11mm), any off-axis guider (e.g., 17.5mm), and other T2 spacers to precisely equal the 55mm required by your flattener.

    I'm connecting my ZWO camera to a Celestron reducer; is the PrimaLuceLab 7mm T2 Extension all I need?

    It's unlikely to be the only piece you need. The 7mm extension provides part of the required spacing. You must calculate the total distance required by your reducer and subtract the camera's flange distance and the thickness of any other adapters to see what remaining gap the 7mm extension helps fill.

    Can I stack multiple PrimaLuceLab 7mm T2 Extensions?

    Yes, these extensions are designed to be screwed together. You can stack them to achieve multiples of 7mm (e.g., 14mm, 21mm). For more precise adjustments, you can add other T2 spacers between them.

    What is the purpose of the knurling on the PrimaLuceLab 7mm T2 Extension?

    The knurled finish provides a textured surface for a better grip. This makes it much easier to thread the extension on and off, especially in cold weather when you might be wearing gloves or when threads are tight.

    Will the inside of the PrimaLuceLab 7mm T2 Extension cause reflections in my images?

    No, the interior is black anodized specifically to create a non-reflective matte surface. This prevents stray light from bouncing around inside your imaging train and reducing the contrast of your final image.

    What threads does the PrimaLuceLab 7mm T2 Extension use?

    It uses the standard T2 thread (M42x0.75mm). One side has a male T2 thread, and the other has a female T2 thread, allowing it to be inserted anywhere in a standard T2-threaded imaging train.

  • Length 7mm
    Threads T2 (M42x0.75mm) Male/Female
    Material Anodized Aluminum

    • PrimaLuceLab 7mm T2 Extension

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  • PrimaLuceLab 1-Year Warranty