The B+W Filters 37mm Infrared Filter is used for blocking the entire visible spectrum.You can capture pure infrared photographs without the visible red component using this camera lens filterThe light transmission through this filter exceeds 1% at 800nm and rises to 88% at 900nmThe B+W 093 IR Glass Filter is used in the scientific field, materials research, and forensics frequentlyDepending on the illumination and characteristics of the film, the filter factor of the B+W Filters 37mm Infrared Filter varies