MRC, short for “Multi-Resistant Coating,” is a technology developed by Hoya. This nano-coating refers to a system of several thin layers applied to the glass of a photographic filter. The primary function of these layers is to reduce light reflections on the filter’s surface, thereby minimizing unwanted effects such as glare or ghosting, while also increasing the amount of light that reaches the camera’s sensor. The hardened layers also increase the filter’s scratch resistance. The final nano-coating gives the surface hydrophobic and oleophobic properties, meaning it repels both water and grease. This makes it significantly easier to clean the filter of fingerprints, raindrops, and other contaminants.