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Starizona M42 Extension - 3mm

Starizona M42 Extension - 3mm

by Starizona
SKU STZ-EXTM42-3
CA$10.00 - CA$10.00
CA$10.00
CA$10.00 - CA$10.00
CA$10.00
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  • Adds 3mm of spacing to an imaging train
  • Features M42 male and female threads
  • Solid, fixed-length design
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  • Description
  • FAQ
  • Specifications
  • Warranty

  • Starizona M42 Extension - 3mm

    The Starizona M42 Extension provides a simple, rigid solution for adding exactly 3mm of length to an M42-threaded imaging train. This fixed-length spacer is designed to help you achieve the precise back focus required by your field flattener or focal reducer, ensuring sharp stars across your entire image sensor. By threading directly into your existing setup, it offers a secure connection for fine-tuning your optical spacing.

    Precision Spacing: The 3mm Back Focus Solution

    Achieving perfect back focus is critical for astrophotography, and often the final adjustment needed is only a few millimeters. The Starizona 3mm M42 Extension is the ideal tool for this scenario. When your stars are sharp in the center but slightly elongated in the corners, it's a clear sign that your camera sensor is not at the optimal distance from your corrector lens. This spacer bridges that small gap with a solid, non-flexing component, which is often preferable to variable spacers that can introduce tilt. With standard male and female M42 threads, it integrates seamlessly into most common imaging setups.

  • What is the primary use for the Starizona M42 Extension - 3mm?

    This extension is used to add a precise 3mm of distance in an astrophotography imaging train. This helps you achieve the exact back focus distance specified by a focal reducer or field flattener, which is necessary for creating sharp, point-like stars across the entire field of view.

    What threads does the Starizona M42 Extension use?

    The extension features standard M42 threads, with one male side and one female side. This allows it to be inserted between two other M42-threaded components, such as a camera T-ring and a reducer.

    Why use a fixed 3mm Starizona M42 spacer instead of an adjustable one?

    When you know you only need a small, specific amount of spacing like 3mm, a fixed spacer provides a more rigid and stable connection. Unlike some adjustable spacers, a solid extension has zero chance of introducing optical tilt, ensuring your camera sensor remains perfectly perpendicular to the light path.

  • Threads M42 (male/female)
    Extension Length 3mm
  • Starizona Warranty