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The Sky-Watcher high-performance refractor offers premium optical performance for the discriminating amateur astronomer. Refractor is coveted for the superb contrast, high-definition and coal-black sky background that make stars appear like diamonds imbedded in black velvet. SW refractor utilizes the most modern optical glasses and fabricating techniques to deliver the ultimate in high-fidelity astronomical imaging.
Subtle details pop as never seen before in telescopes of lesser optical capability. Sky-Watcher's Crown (BK7) and Flint (F2) achromatic lenses are fabricated to the highest optical standards from Grade-A glass free of striae and other image-degrading imperfections. Each lens set is individually pitch-polished and hand figured by a master optician ensuring diffraction-limited premium optical performance that is second to none worldwide. All lenses are uniformly air-spaced. This attention to detail and striving for perfection ensures the amateur astronomer peak performance and a great experience each and every time a Sky-Watcher refractor is taken into the field.
Select models of large refractors will benefit from the inclusion of Schott glass being used for the positive front Crown element in the objective. Schott is the recognized world leader in glass utilized for precision optical lens systems, including medical instrumentation and famous-brand camera lenses. While Schott glass is only used in selected models, all other models utilize top-quality, Grade-A glass from perhaps less famous but, nonetheless, highly respected, high-quality glass manufacturers.
Each optical lens surface is coated with exotic anti-reflection metallic coatings (fully coated) to ensure the optimum light through-put. Four layers are applied to each surface (Magnesium Fluorite, MgF2 and Hafnium Dioxide, HfO2). The proprietary Sky-Watcher "Metallic High-Transmission Coatings" (MHC) are the finest light anti-rejection coatings in their class.