William Optics 1.25"
90degree Dura Bright Dielectric Diagonal
Experience a significant boost in image brightness, contrast, and overall clarity when compared to basic diagonal options!
Equipped with a Dura-Bright thick mirror and advanced dielectric mirror coatings delivering an impressive 99% reflectivity.
Precision-polished to 1/12 lambda surface accuracy.
12mm thick mirror substrate for superior optical performance.
Threaded for compatibility with 1.25" filters.
Features a compression ring to prevent damage or marks on eyepiece barrels.
Integrated internal safety stop ensures that 1.25” eyepiece barrels never touch the mirror surface.
Presenting the 2014 edition of the William Optics Dura-Bright Diagonal — a remarkable innovation in the evolution of mirror star diagonals! This 90° 1.25" mirror-style star diagonal includes a high-grade Dura-Bright thick mirror, enhanced with dielectric mirror coatings offering 99% reflectivity. The result? Improved contrast and fine resolution, especially valuable during planetary, lunar, and double-star observations.
The Dura-Bright also boasts authentic 100% real carbon fiber side panels, lending a sophisticated, premium finish to your telescope setup.
The WO 1.25" Dura-Bright Diagonal has been expertly engineered with distinct features for superior functionality and enduring performance.
Top-Notch Performance & Brightness
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Dielectric coating provides ultra-high 99% reflectivity.
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12mm thick, high-precision mirror substrate ensures outstanding image stability.
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Polished to exacting 1/12th wave surface accuracy.
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Designed for permanent alignment — no need for future adjustments.
Meticulous Craftsmanship
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Secure locking screw for eyepiece and adapter placement.
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Oversized knurled thumbscrews — easy to grip, even with gloves.
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Threaded to support 1.25" standard filters.
Striking Design
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Patented and elegant aesthetics.
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Precision-machined from premium-grade aluminium.
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Internal anti-reflective baffling ensures maximum contrast.
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Side panels crafted from real carbon fiber — adds style and functionality.
Superbly Constructed for Long-Term Use
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Compression rings included (on both diagonal and adapter) — protect against barrel scratches.
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Built-in internal safety stop prevents 2" eyepieces from contacting the mirror.
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Ideal for pairing with high-end telescopes and precision optics.
| Feature |
Details |
| Reflectivity |
Ultra-High Dielectric with 99% reflectivity |
| Mirror |
Precision 1/10 lambda surface, 12mm thick for top-tier optical quality |
| Accessories |
Includes 2"-1.25" adapter with brass compression ring |
| Measurements |
48mm inside diameter, threaded to support a wide range of filters |
| Weight |
210g |
