The Protector protects the lens surface from dirt and dust, as well as scratches. It is an ideal filter for regular use as it is completely colorless so it does not affect color reproduction.
By incorporating SIGMA'ｓ Super Multi-Layer Coating, the filter reduces flare and ghosting. In addition, black rimmed glass eliminates unnecessary internal reflections, and provides high performance for both digital cameras and film cameras.
Low-profile filter rim prevents vignetting with wide-angle focal length lenses.
Non-slip mounting and removal of filter.
SIGMA has checked the compatibility of all SIGMA filters with all SIGMA lenses. In addition, SIGMA has confirmed that these filters allow light to pass through evenly throughout the image, from the center to the edges. All SIGMA lenses in its new lines are checked with SIGMA's proprietary Modulation Transfer Function (MTF) measuring system (A1)* using 46-megapixel Foveon direct image sensors, and all SIGMA filters are also manufactured to meet this same exacting standard.
The storage case is made of a special acrylic that is both stronger and more flexible than conventional filter storage case materials. The outer acrylic case is molded so as to be integrated with the inner elastomer holder, creating a filter holder designed to last many years with minimal deterioration. The case is designed to be highly durable and not open or close accidentally during use. All of these individual benefits add up to a case that is ideal for filter storage.
All SIGMA filters are made completely in Japan, including all individual processes applied in their manufacture.