SM103

Sigma Filter 105 mm WR ceramic protector

The SIGMA WR CERAMIC PROTECTOR is the first professional optical protection filter in Clear Glass Ceramic (transparent glass ceramic), capable of protecting your lenses to the maximum without reducing their effectiveness (MTF test on Sigma Global Vision Series lenses), maintaining the transmittance index of the original light.
To create it, Sigma relied on a specialized glass manufacturer, Ohara Inc. (All Made in Japan).
Glass ceramic is used in industry, including aerospace, and used, in this case, for an optical filter with much superior performance to conventional glass filters, both in terms of hardness and resistance to scratches, water, oil and dust.

As regards hardness, the difference lies in the fact that microcrystals are used which are uniformly immersed in depth through a special glass heating process, while traditional protective filters, even reinforced ones, are only immersed on the surface.
Also in terms of resistance, the filter obtained with Clear Glass Ceramic technology is ten times more resistant than a common protective filter and three times more resistant than a reinforced glass filter, as well as giving superior flexibility to the sapphire crystal.

It resists, for example, small breakages due to small scratches or splinters, and reducing the risk of chipping also means greater safety.
The finished product is also lighter and thinner, even compared to Sigma's own filters, by 30% and 50% respectively.
As regards the Water Repellent (WR) property, Sigma declares that water drops "bounce back" from the glass-ceramic filter, the light is only reflected at 0.24%, reducing glare and ghosting, fingerprints are removed with one wipe , the scratch resistance is ten times higher than that of glass treated with Sigma Super Multi-layer coating. The coating also has an antistatic function, and therefore reduces the attraction of dust particles on the surface of the filter, which are however easy to remove.
The WR Ceramic Protector filter case is also "coordinated" (from a technological point of view) with the filter itself: resistant and flexible acrylic exterior, shaped to adapt to the internal elastic support, and made to last, and not to open or close accidentally.
diameter: 105 mm