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Starizona M48 Extension - 20mm
Starizona M48 Extension - 20mm
Starizona M48 Extension - 20mm
Starizona M48 Extension - 20mm

Starizona M48 Extension - 20mm

by Starizona
SKU STZ-EXTM48-20
$40.00 USD - $40.00 USD
$40.00 USD
$40.00 USD - $40.00 USD
$40.00 USD
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  • Adds 20mm of spacing to an imaging train
  • Features male and female M48 threads
  • Ensures precise back focus adjustment
  • Rigid, single-piece construction
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  • Description
  • FAQ
  • Specifications
  • Warranty

  • Starizona M48 Extension - 20mm

    The Starizona M48 Extension adds a precise 20mm of length to an M48-threaded imaging train. This single-piece tube is designed to bridge a 20mm gap between components, ensuring you can achieve the critical back focus distance required by your specific field flattener or focal reducer.

    M48 Spacing for 20mm of Back Focus

    Achieving a perfectly flat field of view depends on placing your camera's sensor at the exact back focus distance specified by your optical corrector. This Starizona extension provides a fixed 20mm of spacing, making it a crucial component for hitting that target. By threading its male M48 connection into a female M48 port on your reducer or other accessory, you create a rigid, non-flexing segment in your optical train. You can combine this 20mm extension with other spacers to dial in the exact distance your system requires.

  • What is the primary purpose of the Starizona M48 20mm Extension?

    The Starizona M48 20mm Extension is used to add exactly 20mm of distance within an M48-threaded imaging train. This is essential for achieving the correct back focus—the specific distance required between a focal reducer or field flattener and the camera sensor for sharp, coma-free stars across the entire image.

    My corrector requires 55mm of back focus, and my camera's flange is 35mm from the sensor. Will this 20mm extension work?

    Yes, in that scenario, the Starizona M48 20mm Extension is the perfect solution. You have a 20mm gap to fill (55mm required - 35mm existing = 20mm needed), and this extension is designed to fill that exact space, assuming all your components use M48 threads.

    Can I connect the Starizona M48 Extension directly to an M42 T-ring?

    No, not directly. The Starizona 20mm Extension uses M48 threads, which are larger than the M42 threads found on standard T-rings. To connect them, you would need a separate M48-to-M42 step-down adapter, which would also factor into your total back focus calculation.

  • Thread Type M48 (Male/Female)
    Extension Length 20mm
  • Starizona Warranty