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Starizona M42 Extension - 5mm

Starizona M42 Extension - 5mm

by Starizona
SKU STZ-EXTM42-5
$6.95 USD - $6.95 USD
$6.95 USD
$6.95 USD - $6.95 USD
$6.95 USD
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  • Adds 5mm of Spacing to an Optical Train
  • M42 Male and Female Threads
  • Rigid Mechanical Extension for Back Focus
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Starizona M42 Extension - 5mm

    The Starizona M42 Extension adds exactly 5mm of spacing to any optical train using standard M42 threads. This male-to-female threaded tube is a simple, rigid solution for precisely setting the back focus distance between your camera and field flattener or reducer, which is critical for achieving sharp stars across the entire image frame.

    Achieving 5mm of Precise Back Focus

    Every optical corrector, from field flatteners to coma correctors, requires a specific distance to the camera sensor for optimal performance. The Starizona 5mm extension is a fundamental building block for hitting that target. By inserting this spacer into the M42-threaded path, you add a fixed, non-flexing 5mm to your total back focus. This is often used in combination with other spacers to fine-tune the distance required by your specific imaging setup, ensuring your system is correctly configured for edge-to-edge sharpness.

  • What is the purpose of the Starizona M42 5mm Extension?

    It adds exactly 5mm of length to an M42-threaded imaging train. This helps you achieve the precise back focus distance required by your flattener, reducer, or coma corrector for optimal optical performance.

    How would I use the Starizona 5mm extension in my imaging train for a refractor with a flattener?

    You would thread the 5mm extension between your M42-threaded components, such as between the flattener and an off-axis guider or filter wheel, to add the necessary spacing. Its male and female M42 threads allow it to fit directly in the optical path without additional adapters.

    Can I use this Starizona extension to help reach the 55mm back focus needed for my SCT corrector?

    Yes, the 5mm M42 extension is a common component for building up to a standard 55mm back focus distance. You would typically combine it with other M42 spacers, T-adapters, and the camera's own flange distance to reach the exact total your specific corrector requires.

  • Thread Type M42 (Male/Female)
    Extension Length 5mm

    • Starizona M42 Extension - 5mm

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  • Starizona Warranty