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Starizona M42 Extension - 7mm

Starizona M42 Extension - 7mm

by Starizona
SKU STZ-EXTM42-7
$6.95 USD - $6.95 USD
$6.95 USD
$6.95 USD - $6.95 USD
$6.95 USD
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  • Adds 7mm of spacing
  • M42 Male and Female Threads
  • Essential for Correcting Back Focus
  • Rigid, Single-Piece Construction
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Starizona M42 Extension - 7mm

    The Starizona M42 Extension adds a precise 7mm of spacing to any imaging train using standard M42 male/female threads. This component is a simple, rigid solution for achieving the exact back focus distance required by your camera and optical corrector, ensuring your optical system performs as designed.

    Achieving 7mm of Critical Back Focus

    Every field flattener, coma corrector, or focal reducer has a specific, optimal distance to the camera sensor—known as back focus. Deviating from this distance can introduce image-degrading aberrations like elongated stars at the edge of the field. This 7mm extension is a fundamental tool for fine-tuning that critical spacing.

    When assembling your camera, filter wheel, and off-axis guider, you often end up just a few millimeters short of the ideal back focus. The Starizona M42 Extension - 7mm bridges that gap. It threads securely between any two M42 components, adding a fixed length to dial in your spacing and achieve a perfectly flat, sharp field of view from corner to corner.

  • What is the purpose of the Starizona M42 Extension - 7mm?

    Its sole purpose is to add exactly 7mm of length to an M42-threaded imaging train. This is done to help achieve the precise back focus distance required by a focal reducer, field flattener, or coma corrector for optimal imaging performance.

    What threads does the Starizona 7mm Extension use?

    The extension uses standard M42 threads. It has male threads on one side and female threads on the other, allowing it to be inserted between any two compatible M42 accessories, such as a camera T-ring and a filter wheel.

    How long is this Starizona M42 extension tube?

    This extension tube provides exactly 7mm of additional length. Starizona manufactures M42 extensions in various lengths to meet different spacing requirements.

  • Thread Type M42 (Male/Female)
    Extension Length 7mm

    • Starizona M42 Extension - 7mm

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  • Starizona Warranty