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RB Focus Aperture Ring for Newtonian Telescopes

RB Focus Aperture Ring for Newtonian Telescopes

by RB Focus
SKU RB-APRING-150
$28.99 - $40.99
$28.99
$28.99 - $40.99
$28.99
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  • Designed for 150 mm, 200 mm, and 250 mm Newtonians
  • Removes the helix-shaped reflections caused by mirror clips
  • Masks Primary Mirror Retaining Clips
  • Simple Installation
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • RB Focus Aperture Ring for Newtonian Telescopes

    The RB Focus Aperture Ring for Newtonian Telescopes is made for 150 mm, 200 mm and 250 mm reflectors. It covers the clips that hold the primary mirror in its cell, which RB Focus identifies as the cause of the helix-shaped reflections that appear around stars in addition to the diffraction spikes.

    Clean Diffraction Patterns on 150, 200, and 250 mm Newtonians

    If you have seen helix-shaped reflections around stars, separate from the diffraction spikes, RB Focus explains that they come from the clips that hold the mirror to its cell.

    The aperture ring covers the clips and, as RB Focus states, solves the problem completely. RB Focus describes it as very simple to install.

  • What causes the extra reflections the RB Focus Aperture Ring fixes?

    The strange, helix-shaped reflections are caused by the small metal clips that hold the primary mirror in its cell. These clips protrude slightly into the telescope's light path, creating their own unique diffraction artifacts. The RB Focus Aperture Ring masks these clips, eliminating the unwanted reflections and leaving only the clean diffraction spikes from the secondary mirror's spider vanes.

    How do I install the RB Focus Aperture Ring?

    RB Focus describes it as very simple to install: the ring covers the primary mirror clips. RB Focus gives no further installation details.

    Do I need a specific RB Focus Aperture Ring for my telescope's aperture?

    Yes. Choose the size that matches your telescope's aperture: 150 mm, 200 mm or 250 mm.

  • Purpose Covers the primary mirror clips
    Sizes For 150, 200 and 250 mm aperture reflectors

    • Aperture ring

      × 1

  • RB Focus 2-Year Warranty