Astro-Tech Mirror Diagonal

This diagonal is designed for use with refractors, Schmidt-Cassegrain, and Maksutov-Cassegrain telescopes. It features a 2-inch barrel size, making it a versatile upgrade for most standard focusers.

No, it is designed to prevent that. The included 1.25-inch adapter uses a compression ring rather than a set screw, which secures your eyepiece firmly without scratching or marring the barrel.

The 46-layer dielectric coating provides 99% reflectivity, which is significantly higher than standard aluminum coatings. This results in noticeably brighter, higher-contrast images, especially when observing faint deep-sky objects.

The 1/10th wave rating refers to the precision of the mirror's surface flatness. This high level of optical accuracy ensures that the light path remains undistorted, providing the sharp, high-resolution views necessary for detailed planetary and lunar observation.

The safety groove is a machined recess that helps prevent the diagonal from accidentally slipping out of the focuser if the thumbscrew loosens. It provides an extra layer of security for your equipment during a long observing session.

Yes, the interior of the diagonal features anti-reflection threading. This design minimizes stray light bouncing around inside the housing, which helps maintain deep blacks and improves overall image contrast.