Sigma’s new filters use clear glass ceramic to protect your prized lensesView gallery - 2 images
Sigma has revealed a range of lens filters which use a new type of crystallized glass to offer increased protection, while also being thinner and lighter than previous models. The WR Ceramic Protector filters use Clear Glass Ceramic along with a water-repellent coating to keep your prized camera lenses safe, while preserving image quality.
Clear Glass Ceramic, developed with glass manufacturer Ohara Inc, is made using a special heat treatment which evenly precipitates microcrystalline spinel throughout the glass. This gives it a consistent strength, makes it resistant to cracking due to small scratches or chips, and offers very high transmittance, meaning it's suitable for use as optical glass.
Sigma says by producing filters using the new glass, its WR Ceramic Protector range is able to be 10 times stronger than conventional protective filters, and over three times stronger than filters made with chemically hardened glass of the same thickness. The new filters are also said to be up to 50 percent thinner and 30 percent lighter than the firm's previous filters.
The Sigma WR Ceramic Protector filters – which will come in a range of common filter thread sizes from 67 mm to 105 mm – also benefit from a water-repellent coating. This is said to repel both water and oil, meaning fingerprints can be easily wiped off. It also reflects just 0.24 percent of visible light, to help minimize flare and ghosting.
There's no word yet on exactly when the new filters will be available, or how much they will cost.
You can check out a promo video for the new filters below.