Celestron 1.25" Dielectric Mirror Diagonal with Twist-Lock Holder - 93571

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Item #CELE-93571

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  • $129.95
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  • Enjoy improved telescope views by using this premium diffraction-limited 1.25" dielectric mirror diagonal
  • For more comfortable viewing through refractor or Cassegrain-style instruments, an optimal 90º viewing angle is provided
  • 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 improves optical alignment by keeping the eyepiece centered in the diagonal
  • Compatible with all standard accessories such as eyepieces, Barlow lenses, and threaded filters, that have a 1.25" barrel size
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  • Description

    Celestron 1.25" Dielectric Mirror Diagonal


    For guaranteed maximum light transmission without compromising on optical quality, the 1.25" Dielectric Star Diagonal with Twist-Lock from Celestron is an excellent choice. Experience images that are both brighter and sharper by upgrading your existing star diagonal to this premium model.

    By reflecting the telescope's light path 90º, this star diagonal is able to offer increased viewing comfort. Glass surface is over 99% reflective thanks to 58 layers of dielectric coatings to enable the maximum amount of light to reach the eyepiece. 1.25" 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 1.25" barrel stop protects the mirror from being damaged by 1.25" accessories with long barrels.

    The twist lock ring is orange anodized for increased visibility while the remainder of this diagonal’s construction consists of black anodized aluminum. A threaded and flat black painted interior works to prohibit glare. Taken together, the Celestron 1.25” Dielectric Star Diagonal’s features and high-end finishes make it one of the best 1.25” star diagonals ever offered by Celestron in terms of quality.


    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 1.25" Dielectric Mirror Diagonal
    • Twist-Lock Eyepiece Holder

  • Dimensions & Specifications

    • Diagonal Size: 1.25"
    • Diagonal Type: Mirror
    • Glass Material: BK7
    • Coatings: 58 layers dielectric
    • Reflectivity: Over 99%
    • Optical Quality: Diffraction limited
    • Eyepiece Holder: 1.25" Twist-Lock
    • Compression Ring: Yes; one ring
    • Housing: Black anodized machined aluminum
    • Barrel Interior: Glare threaded and painted flat black
    • Filter Threads: Yes; 1.25"
    • Dimensions: 4.5" x 2" x 3.5" (114.3mm x 50.8mm x 88.9mm)
    • Weight: 7.5 oz. (0.5 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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