What is the advantage of the William Optics Dura-Bright's 99% dielectric coating?
The 99% dielectric coating ensures that virtually all light gathered by your telescope reaches your eyepiece. This results in brighter, higher-contrast images compared to standard aluminum or silver coatings, which is especially critical for observing faint planetary details, deep-sky objects, and the subtle color differences in stars.
Why doesn't the William Optics Dura-Bright diagonal have collimation screws?
The absence of collimation screws is a design feature, not a limitation. William Optics builds the Dura-Bright diagonal with such high mechanical precision that it is guaranteed to hold its alignment permanently. Diagonals that offer adjustments often do so because their construction is less robust and can shift over time; the Dura-Bright's patented, solid design eliminates this possibility.
Will the Dura-Bright diagonal scratch my eyepiece barrels?
No. Both the main 2" holder and the included 1.25" adapter use brass compression rings. Unlike simple lock screws that dig into the eyepiece barrel, a compression ring provides a secure, even grip around the entire barrel, preventing any cosmetic damage or marring.
How does the 12mm thick mirror in the Dura-Bright help when observing Jupiter with my FLT-132?
The 12mm thick mirror substrate provides superior thermal stability. When observing an object like Jupiter for an extended period, especially as your telescope adjusts to ambient temperature, a thinner mirror could slightly deform and soften the image. The Dura-Bright's thick mirror resists these changes, ensuring your view of the Great Red Spot and its cloud bands remains sharp and stable all night.
Can I use 1.25" eyepieces with the 2" William Optics Dura-Bright diagonal?
Yes, absolutely. The diagonal comes with a high-quality 2" to 1.25" adapter. This adapter also features a compression ring, so your 1.25" eyepieces are held just as securely and safely as your 2" eyepieces.
Is the Dura-Bright a good choice for splitting close double stars like Epsilon Lyrae with a GT102?
Yes, it's an excellent choice. Splitting tight doubles like the "Double Double" Epsilon Lyrae requires maximum image contrast and sharpness. The Dura-Bright's 1/12th wave mirror and 99% reflectivity coatings preserve the delicate Airy disk and diffraction rings of the stars, making it easier to achieve a clean separation at high magnification with a high-end refractor like the GT102.
