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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 M48 Spacer 1mm

PrimaLuceLab M48 Spacer 1mm

by PrimaLuceLab
SKU PLL-PL3304801
$9.00 - $9.00
$9.00
$9.00 - $9.00
$9.00
Price Match Policy!
  • Precise 1mm Thickness
  • M48x0.75 Female Thread
  • Fine-Tunes Back Focus Spacing
  • Used with M48 Extension Tubes
  • Prevents Star Elongation at Field Edge
1 in stock
Qualifies for FREE Shipping in CONUS on orders over $350.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • PrimaLuceLab M48 Spacer 1mm

    The PrimaLuceLab M48 Spacer provides a precise 1mm shim for M48-threaded accessories, allowing you to achieve exact back focus spacing in your imaging train when standard extension tubes fall just short.

    Fine-Tuning Back Focus: The Critical 1mm Adjustment

    Achieving the perfect distance between your field flattener or reducer and the camera sensor is non-negotiable for sharp, round stars across the entire frame. When your combination of extension tubes leaves you with a tiny but critical gap, this 1mm spacer closes it without introducing flexure or alignment issues. It's the essential component for correcting minor spacing errors that cause distorted stars at the edge of your images.

    1mm vs. 0.5mm Spacers: Selecting the Right Increment

    PrimaLuceLab offers M48 spacers in both 1mm and 0.5mm thicknesses to cover different needs. This 1mm spacer is ideal for making a noticeable adjustment when you're confident in the approximate size of your spacing gap. For situations requiring even more granular control, where you are dialing in the distance with extreme precision, the 0.5mm version may be a better choice. Many imagers keep both on hand to solve any back focus challenge.

  • What is the PrimaLuceLab M48 Spacer 1mm used for in an imaging train?

    The PrimaLuceLab M48 Spacer 1mm is used to make fine adjustments to the back focus distance between an optical corrector (like a flattener or reducer) and the camera sensor. It adds exactly 1mm of length to an M48-threaded connection to ensure stars are perfectly focused across the entire field of view.

    When would I need a 1mm spacer instead of another M48 extension tube?

    You need a 1mm spacer when your existing M48 extension tubes get you very close to the correct back focus, but not exactly there. If the next size up for an extension tube is too long and causes star bloat, this thin spacer provides the small, precise increment needed to nail the spacing perfectly.

    Can I stack multiple PrimaLuceLab 1mm M48 spacers?

    Yes, you can stack multiple spacers to achieve a custom distance (e.g., two spacers for 2mm). However, for larger gaps, it is always mechanically better to use a single, solid M48 extension tube of the correct length to minimize potential tilt in the imaging train.

    How do I know if I need this 1mm spacer for my Celestron EdgeHD reducer?

    After setting up your imaging train to the manufacturer's recommended back focus, take a test image. If you notice that stars in the corners are slightly elongated, you likely have a small spacing error. Adding or removing a 1mm spacer is a common method to test and correct this, aiming for perfectly round stars from the center to the edge.

    Is the PrimaLuceLab M48 spacer threaded?

    No, the spacer itself is not threaded. It is a flat, 1mm thick ring that you place between two M48-threaded components, such as an extension tube and a camera adapter. The male threads of one component pass through the spacer to engage with the female threads of the other.

    Does this M48 spacer work with accessories from other brands?

    Yes. The M48x0.75 thread is a standard in astrophotography. This 1mm spacer will work with any M48-threaded extension tubes, flatteners, off-axis guiders, or camera adapters from any manufacturer that adheres to this standard.

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  • PrimaLuceLab 1-Year Warranty