The HOYA UV&IR Cut is a specialized filter that has the ability to cut both UV rays below 390nm and IR rays above 700mn leaving just the light rays in the visible spectrum passing through the filter and into the camera. Filter is available in sizes 49mm through 82mm. This filter is used on a digital camera and the video, which do not have an IR protection filter toward an image sensor or were remodeled. This is important because unfiltered CCD and CMOS sensors are extremely susceptible to UV and IR rays just outside the visible spectrum that can have a very negative impact on image quality. PLEASE NOTE: The UV-IR Cut filter is intended for use with digital SLR cameras and cine cameras that do NOT have an IR filter installed in front of the sensor. Color balance effects can occur when this filter is used with cameras that have an IR filter installed in front of the sensor. Please consult your camera owner's manual before use. The HOYA UV & IR light transmission curve shows the sharp-cut nature of the filter glass and coatings as well as the consistent light transmission in the visible spectrum. This curve demonstrates a more even visible light transmission than the closest competitor. This means that sharper images with more depth and finer, richer color gradations are possible with the HOYA UV & IR Cut filter. The effect of the filter is achieved mainly though the multi-layer coatings on the surface of the filter. Hoya begins with crystal clear, colorless optical glass and then bonds coating to this filter that block both UV and IR light rays outside of the range mentioned. There is light incidence angle dependence in the transmission factor because overlayer is thick, so this filter doesn't suit use by a wide-angle lens. It is suitable for heavenly body photography. AN IMPORTANT NOTE REGARDING WIDE-ANGLE LENSES Increasing the angle of incidence, meaning light rays entering the filter from an extreme angle as is the case with super-wide and ultra-wide angle lenses, leads to an increasing color shift as the angle increases. This is based on the physics of light and the nature of the coatings. All UV-IR cut filters have the same properties in this regard. It is not recommended this filter be used with lenses having a field of view greater than 60 degrees.