The angled viewing 20-60x60 Diamondback Spotting Scope from Vortex features specialized optical coatings to provide bright and clear images, while utilizing a relatively small objective lens. All air-to-glass surfaces have Vortex's XR anti-reflective coatings to minimize light loss. Additionally, they are ArmorTek coated for scratch resistance. To ensure accurate color across the entire visible spectrum, the Porro prisms are dielectric coated. These coatings are highly reflective and lose less than 1% of the light that passes through them. The use of Porro prisms creates an improved depth of view over roof prisms. This combination of coatings and optics creates a spotting scope that produces bright, clear, highly contrasted images with accurate color transmission.