

Celestron Dielectric Star Diagonal with Twist-Lock (1.25-Inch)
Key item features
- Enjoy better views through your telescope with this premium diagonal featuring diffraction-limited optics and dielectric coatings
- Provides a 90° viewing angle, perfect for more comfortable viewing through refractor and Cassegrain-type telescopes
- 58 layers of dielectric coatings provide an over 99% reflective surface, ensuring the maximum amount of light collected by the telescope reaches the eyepiece
- Twist-lock keeps the eyepiece centered in the diagonal to provide better optical alignment
- Accepts standard eyepieces, Barlow lenses, threaded filters, and other accessories with a 1.25” barrel
Specs
- Field of view90º
- BrandCelestron
- Lens diameter0 mm
- Skill levelBeginner
- Weight0.6 lb
- Dimensions5.20 x 4.30 x 3.80 in
- Free shipping
Free 30-day returns
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About this item
Product details
Ensure maximum light transmission without loss of optical quality with the Celestron Dielectric Star Diagonal, 1.25-inch with Twist-Lock. Upgrade your existing star diagonal to this premium one and enjoy brighter, sharper images without replacing your telescope. 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 an over 99% reflective surface, delivering the maximum amount of light to the eyepiece.
Twist-Lock Features
The twist-lock eyepiece holder secures any 1.25-inch eyepieces while keeping them centered in the diagonal, thus providing best opto-mechanical alignment between the telescope and eyepiece. Unlike traditional thumb screws, the twist-lock cannot scratch or engrave the barrel of your eyepieces. The twist-lock has an integrated 1.25-inch barrel stop that prevents 1.25-inch accessories with long barrels from damaging the mirror. All the diagonal’s mechanical parts are made of machined black anodized aluminum, except the twist lock rings, which are orange anodized for visibility. The interior of the barrel is glare threaded and painted flat black to prevent glare. With all its features and these high-end finishes, the Celestron Dielectric Star Diagonal, 1.25-inch with Twist-Lock is one of the highest quality 1.25-inch star diagonals that Celestron has ever offered.
Dielectric Star Diagonal Advantages
The key specifications for a star diagonal are its reflectivity and its optical quality. This diagonal delivers top performance in both categories, with an over 99% reflective mirror and diffraction-limited optical quality. This ensures that virtually all the light collected by the telescope will reach the eyepiece without the diagonal affecting optical performance. Using a lower quality star diagonal can both dim the view and degrade optical quality. You can enjoy better views from your telescope by simply swapping out its diagonal for a premium one, like the Celestron Dielectric Star Diagonal.
- Enjoy better views through your telescope with this premium diagonal featuring diffraction-limited optics and dielectric coatings
- Provides a 90° viewing angle, perfect for more comfortable viewing through refractor and Cassegrain-type telescopes
- 58 layers of dielectric coatings provide an over 99% reflective surface, ensuring the maximum amount of light collected by the telescope reaches the eyepiece
- Twist-lock keeps the eyepiece centered in the diagonal to provide better optical alignment
- Accepts standard eyepieces, Barlow lenses, threaded filters, and other accessories with a 1.25” barrel


