Celestron 2" Dielectric Mirror Diagonal with Twist-Lock Holder - 93573

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Item #CELE-93573

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  • Combining diffraction-limited optics and dielectric coatings, this premium 2" diagonal significantly improves the views observers experience through a telescope
  • With a 90º viewing angle, this diagonal facilitates comfortable viewing with refractor or Cassegrain-style telescopes
  • Over 99% surface reflectivity thanks to 58 layers of dielectric coatings ensures that the greatest amount of light accumulated by the telescope ends its journey at your eyepiece
  • Twist-lock adapter keeps inserted eyepieces centered in the diagonal to improve optical alignment
  • Included 1.25" stepdown adapter allows this diagonal to fit all 2" and 1.25" barrel eyepieces, Barlow lenses, threaded filters, and more
  • Comes with two interchangeable adapters for switching between Schmidt-Cassegrain threads and a 2" barrel adapter, making this diagonal suitable for use with a wide variety of telescopes
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  • Description

    Celestron 2" Dielectric Mirror Diagonal


    Ensure maximum light transmission without compromising optical quality by upgrading your existing star diagonal to this premium Celestron 2" Dielectric Star Diagonal with Twist-Lock. With the telescope you already own and this diagonal, you can enjoy bright views with sharp detail. No need to purchase an entirely new optical system to get a better view.

    This star diagonal reflects the telescope’s light path 90° to provide a more comfortable viewing angle. In addition, the glass has 58 layers of dielectric coatings, which provide a more than 99% reflective surface, delivering the maximum amount of light to the eyepiece. Plus, the included 1.25" stepdown adapter enables compatibility with larger 2" eyepieces for an expanded field of view, along with standard 1.25" eyepieces.

    2" eyepieces are kept secure and centered in the diagonal by the twist-lock holder for optimal opto-mechanical alignment between telescope and eyepiece. Twist-lock is unable to scratch or engrave your eyepiece barrel unlike conventional thumb screws. A built-in 2" barrel stop protects the mirror from being damaged by 2" accessories with long barrels.

    Except for the twist lock ring which is orange anodized to enhance visibility, this diagonal’s construction consists of black anodized aluminum. Both the SCT adapter and 2" barrel interior are glare threaded and painted flat black to minimize glare. Taken together, the Celestron 2” Dielectric Star Diagonal’s features and high-end finishes make it one of the best 2” star diagonals ever offered by Celestron in terms of quality.

    Two interchangeable barrels are also included with this diagonal to enable the flexibility necessary for connection to a wide range of telescopes without the need for supplemental adapters. A standard 2" barrel is included for telescopes, such as refractors, that accept 2" barrels in their focuser, while an SCT threaded barrel is included for Schmidt-Cassegrain telescopes. Each barrel threads onto the diagonal housing for secure attachment to the diagonal.


    Standard Star Diagonals vs Dielectric Star Diagonals


    Reflectivity and optical quality are the key specifications for a star diagonal. This dielectric diagonal delivers top performance in both categories, with an over 99% reflective mirror and diffraction-limited optical quality to ensure that virtually all the light collected by the telescope reaches your eyepiece without the diagonal having an impact on optical performance. Using a lower quality star diagonal can both dim the view and degrade optical quality. You can instantly improve the views you experience through your telescope by simply swapping out its diagonal for a premium Celestron Dielectric Star Diagonal.





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    What's Included

    • Celestron 2" Dielectric Mirror Diagonal
    • Twist-Lock Eyepiece Holder
    • 1.25" Stepdown Adapter
    • SCT Adapter
    • Covers

  • Dimensions & Specifications

    • Diagonal Size: 2"
    • Diagonal Type: Mirror
    • Glass Material: BK7
    • Coatings: 58 layers dielectric
    • Reflectivity: Over 99%
    • Optical Quality: Diffraction limited
    • Eyepiece Holder: 2" Twist-Lock
    • 2" to 1.25" Stepdown Adapter: Included
    • Compression Ring: Yes; two rings for 2" eyepiece holder and one ring for 1.25" stepdown adapter
    • Housing: Black anodized machined aluminum
    • Barrels: Comes with 2" barrel and SCT adapter
    • Barrel Interior: Glare threaded and painted flat black
    • Filter Threads: 2" barrel and 1.25" stepdown adapter have 2" threads
    • Dimensions: 6" x 3" x 4" (152.4mm x 76.2mm x 101.6mm)
    • Weight: 19 oz. (1.2 lbs.)

  • Product Guarantee

    We stand behind all the products we sell, and your satisfaction is our top priority. If you're not satisfied with the quality of your purchase, simply send the item back to us in its original packaging within 30 days of its delivery.

    Manufacturer Warranty

    2 years

    Return & Exchange Policy

    At our site, returns are easy! You may return new, unused, and resalable items for a refund or exchange. Simply ensure that the item is returned in its original product packaging within 30 days of delivery.

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