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Starizona M42 Spacer - 7.5mm

Starizona M42 Spacer - 7.5mm

by Starizona
SKU STZ-EXT-M42-75
$14.95 USD - $14.95 USD
$14.95 USD
$14.95 USD - $14.95 USD
$14.95 USD
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  • Adds 7.5mm of Spacing to an Optical Train
  • M42 Male to M42 Female Threads
  • Fixed, Non-Adjustable Length
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Starizona M42 Spacer - 7.5mm

    The Starizona M42 Spacer provides a fixed, precise extension of 7.5mm for imaging trains that use M42 threads. This 7.5mm length is essential for achieving the exact back focus distance required by many field flatteners and focal reducers, ensuring your optical system delivers sharp stars across the entire sensor.

    Achieving Precise 7.5mm Back Focus

    In astrophotography, connecting a camera, filter wheel, and off-axis guider to a telescope often results in an optical path length that doesn't match the specific requirements of your corrector optics. This Starizona spacer closes a 7.5mm gap with a single, rigid component.

    By inserting this M42-to-M42 spacer, you can confidently hit your target back focus without the complexity or potential for tilt that can come from stacking multiple thin shims or using adjustable adapters. It is a simple, robust solution for a very specific and common spacing problem in M42-based imaging systems.

  • What is the function of the Starizona M42 7.5mm Spacer?

    This spacer adds exactly 7.5mm of length to your M42-threaded imaging train. Its purpose is to help you achieve the precise back focus distance (the distance from the corrector lens to the camera sensor) required by your field flattener or focal reducer for optimal performance.

    What are the thread and length specifications for this M42 spacer?

    The Starizona M42 Spacer has M42 threads on both ends (typically male on one and female on the other) and provides a fixed extension length of 7.5mm.

    How do I know if I need a 7.5mm spacer for my setup?

    You need a 7.5mm spacer if the total back focus of your current imaging train (camera flange distance + adapters) is 7.5mm less than the distance required by your flattener or reducer. You can determine this by adding up the specified optical lengths of all components in your train and subtracting that total from the required back focus of your corrector.

  • Thread M42 to M42
    Length 7.5mm

    • Starizona M42 Spacer (7.5mm)

      × 1

  • Starizona Warranty