The Tiffen 5.65 x 5.65" Full Spectrum IRND 1.8 filter is a combination of an infrared control filter and a 1.8 neutral density filter. An IRND is ideal for HD cameras, which have greater sensitivity in low light and, consequently, increased sensitivity to IR contamination. When using a standard neutral density filter to counter the increased light sensitivity offered by the HD sensor, the effects of infrared pollution become more apparent. This filter combines an ND filter with a comparable IR control filter to eliminate infrared light leakage reaching the sensor whilst maintaining the additional exposure benefits of a neutral density filter. This filter is constructed from Water White glass and is manufactured using ColorCore technology, a process that involves laminating the filter substrate between 2 pieces of optical glass and grinding it flat to a tolerance of 1/10,000th of an inch. This filter measures 5.65 x 5.65" / 143.5 x 143.5 mm. - The infrared control filter helps to block infrared pollution affecting the colour fidelity of the image; this allows a wider colour gamut and more accurate colours, particularly noticeable in the darker regions of the image. - The 1.8 neutral density filter provides a 6-stop exposure reduction. - Water White optical glass for excellent clarity. Specifications