Advances in high-index / low-dispersion optical glasses, new barrel materials, and exotic anti-reflection coatings, along with the latest in computer-aided-design / computer-aided-manufacturing), are combined to produce lenses of unprecedented quality. Diamond-cut from crystal-clear, water-white optical glass, Opteka lenses are ground and polished to a precise precision. Because all Opteka lenses are designed and manufactured with the highest possible degree of consistency, you can swap lenses mid-shoot with no discernable variation in color or effect. The unprecedented purity, color saturation and repeatability of Opteka lenses virtually eliminate the need for lab color timing corrections caused by other filters. This puts more creative control where it belongs, in your hands.