Boost your telescope's performance without buying a new one—simply switch to the Celestron Dielectric Star Diagonal, 2” with Twist-Lock. This top-tier star diagonal allows for maximum light throughput while maintaining superb optical clarity, resulting in brighter and sharper images.

This device redirects your telescope’s light path by 90 degrees for more ergonomic viewing. The glass is engineered with 58 layers of dielectric coatings, ensuring a surface that's over 99% reflective. This directs almost all of the light right into your eyepiece. An added perk is its compatibility with larger 2” eyepieces, giving you a more expansive field of view. Of course, you can still use standard 1.25” eyepieces with the included stepdown adapter.

The twist-lock feature keeps eyepieces firmly in place while aligning them precisely within the diagonal, optimizing the optical pathway between your telescope and eyepiece. This system offers an edge over traditional thumb screws as it won’t scratch or scuff your eyepiece barrels. Additionally, an integrated 2” barrel stop safeguards the mirror from any long-barreled 2” accessories.

In terms of build quality, most of the diagonal’s components are crafted from machined black anodized aluminum. However, the twist-lock rings are anodized in orange for easy visibility. To minimize glare, both the Schmidt-Cassegrain adapter and the 2” barrel have interiors that are threaded and painted flat black.

This high-caliber diagonal also features two interchangeable barrels, adding a layer of versatility. It accommodates a range of telescopes without requiring extra adapters. For refractor telescopes that accept 2” barrels, a standard 2” barrel is included. For Schmidt-Cassegrains (SCTs) with threaded focuser connections, an SCT-threaded barrel is also provided. Both options securely thread onto the diagonal housing.

Standard vs Dielectric Star Diagonals

When it comes to star diagonals, the critical factors are reflectivity and optical integrity. This particular model excels in both domains. With its over 99% reflective mirror and optics that are diffraction-limited, it ensures almost all gathered light reaches the eyepiece without compromising the view. Unlike lesser star diagonals, which can dim your view and reduce optical quality, upgrading to the Celestron Dielectric Star Diagonal gives your telescope a noticeable performance boost.

Specifications