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Home Accessories Diagonals Telescope Diagonals For Astronomy Celestron Dielectric Star Diagonal 1.25 Inch
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 inch barrelEnsure maximum light transmission without loss of optical quality with the Celestron Dielectric Star Diagonal, 1.25 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 telescopes 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. The twist-lock eyepiece holder secures any 1.25 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 barrel stop that prevents 1.25 accessories with long barrels from damaging the mirror.All the diagonals 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" with Twist-Lock is one of the highest quality 1.25" star diagonals that Celestron has ever offered.Standard Star Diagonals vs Dielectric Star DiagonalThe 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.
Excellent Diagonal Replacement for stock Diagonal which has noticeably improved image quality. Twist lock mechanism is leap forward for both ease and speed of use. (30/05/2021) Syer Shulver - Suffolk
Amazing! So much better than the one supplied with the Celestron Starsense Explorer DX102. Just the detail is so much clearer (22/04/2021) - South Wales
Great improvement I have replaced the stock diagonal on my Nexstar 5s with this and found a great improvement, with a far clearer image. The quality is very good and the twist to secure the eyepiece really does save time. The normal excellent service from Harrison Telescopes made this an altogether good buy. (28/11/2020) Pete - Essex
Good twist lock feature Used this tonight for the first time on the Celestron Evolution 8HD and got my first good clear view of M42, the Orion Nebula. Super clear. Good solid piece of kit. Twist Lock is easy to use and, in typical Celestron Orange, is easy to find and operate in the dark. (27/03/2020) Steve Allen - Calne, Wiltshire
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