Sigma, who is more known for stellar lensmaking than for their filters, has just announced a straight bonkers new protective filter technology: clear glass ceramic. Sigma says this material is both shock and scratch resistant and was “developed specifically for Sigma in partnership with a glass manufacturer.” The filter is made with a special heat treatment “that evenly precipitates microcrystalline spinel throughout the materials.”
The result is a clear glass ceramic that is 10 times stronger than a conventional protective filter and three times the strength of a chemically strengthened filter. The lens protector also contains WR coating, which repels water, dust and oil, and allows fingerprints to be easily removed. Sigma says the filter is designed to preserve the lens and ensure long-term, top-notch image quality.
The ceramic glass filter has four main features:
- Scratch-resistant – Sigma’s Clear Glass Ceramic offers a Vickers hardness number of 700HV. The strength of the Clear Glass Ceramic is much stronger than chemically strengthen glass and is; 10 times stronger than conventional filters
- Thinner and lighter – This new protector is up to 50 percent thinner and is up to 30% lighter than previous Sigma filters
- High transmittance – Sigma’s Clear Glass Ceramic offers very high transmittance, making it ideal for use as optical glass
- Water- and oil-repellent coating – The water repellent coating reflects only 0.24 percent of visible light, thereby minimizing flare and ghosting. Its ability to repel both water and oil is also excellent, with water drops bouncing right off, and fingerprints easily to remove
This filter is offered in the most popular filter thread sizes, and is compatible with all Sigma lenses and other lenses that accept front filter threads that are 67mm-105mm diameters. No pricing or availability was provided as of yet, so stay tuned for more information in the coming weeks.