While many lenses use flourine coatings on their front elements to make them easier to clean when they get dirty, to protect your front elements from scratches requires a bit more than chemistry.
Sigma’s new Water Repellent Ceramic Protector can do the trick. The new lens filter is made from shock and scratch-resistant clear glass ceramic that’s incredibly strong. Sigma claims it’s 10 times stronger than a conventional lens filter and three times stronger than a chemically strengthened filter.
The lens protector also contains a coating that repels water, dust and oil. It has a Vickers hardness number of 700HV (a diamond clocks in at 10000HV). Despite its protective characteristics, the new filter is 50 percent thinner and 30 percent lighter than earlier Sigma filters.
The company also claims that the clear glass ceramic delivers “very high transmittance” so it’s suitable for optics.
Pricing and availability of the new protective filters wasn’t announced, but Sigma said they would be available in the “most popular filter thread sizes.”
“The new Clear Glass Ceramic protector is the first of its kind and the strongest material used in the industry,” said Mark Amir-Hamzeh, president of Sigma Corporation of America in a statement announcing the product. “It will enable photographers to safeguard their lenses, while maintaining the impressive sharpness offered by high-quality glass, like our Global Vision line of lenses.”