The HOYA R72 infrared filter is specially designed for infrared photography with digital cameras and infrared film. Infrared light begins in the high red range of the visible spectrum at about 750 nm and extends beyond 1000 nm. This light is not visible to the naked eye. When viewed through the R72 filter, it looks almost opaque because the filter only transmits light from the very high red edge of the visible spectrum and infrared light. Infrared photography provides very interesting, sometimes startling and creative results because an object in a scene reflects infrared light differently than normal light. Due to the nature of infrared light, filter factor and exposure compensation are very different from visible light and depend largely on lighting conditions. The Hoya R72 works well with digital cameras, especially mirrorless cameras or DSLRS without an IR cut filter in front of the sensor. (Please check the user manual of your camera). The filter allows light to pass completely at 760 nm - 860 nm. (Infrared spectrum) with a light transmission of 95%. The HOYA R72 is made of high quality Hoya optical glass mounted in a precision machined aluminum frame for rigidity. Consistent quality, made in Japan. Can be combined with colored black and white contrast filters such as the R25 (red), K2 (yellow), O (orange) or other color filters to change color rendition or contrast effects.