<p>Hi<br> Does anyone know what "AUC" stands for? Does anyone know about this?<br />Kogan claims that it's a new B+W filter (maybe they mean updated), but I can't find any info on the Schneider Optics website or on the web at all. Very curious. I'm asking as I need a good variable polarizer and Kogan offered the best price.</p> <h3>B+W XS-Pro AUC Circular Kaesemann Polarizing MRC Nano Filter - 77mm</h3> <p>.</p>