The straight-through viewing Diamondback 20-60x80 Spotting Scope from Vortex features a large objective lens and specialized optical coatings to provide bright and clear images. 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. This combination of coatings and optics creates a spotting scope that produces bright, clear, highly contrasted images with accurate color transmission.