HITECH 150x150mm Firecrest IRND ND 1.2 Filter Description: Firecrest ND is a revolutionary new type of ND filter from Formatt-Hitech. Rather than dyed resin, Firecrest is a carbon metallic coating used to create hyper neutral NDs. The filters are made from 2mm thick Schott Superwite glass, and the multicoating is bonded in the middle to increase scratch resistance. Firecrest Filters are neutral across all spectrums, including UV, visible, and infrared. This 150x150mm Firecrest ND filter reduces light by 4 stops. About Firecrest ND Coating FirecrestND is a quantum leap improvement over all previous generation ND and IRND products and represents the technological state of the art in scientific light modification. Firecrest is a radical departure in how ND filters are manufactured. Previous generation NDs were made by dying resin. Firecrest is not a dying process. Rather, Firecrest is a carbon metallic multicoating process that is applied directly to the glass through an electrolytic process. Circular filters feature the Firecrest coating on the outside, making them anti-reflective and hydrophobic. On rectangular filters, the Firecrest coating is sandwiched between optical glass, increasing scratch resistance and longevity. Firecrest reduces all spectrums of light (UV, visible, near infrared and infrared) almost perfectly evenly. Firecrest filters are made from Schott Superwite glass. Independent Test Data These graphs show test results from an independent test performed at The Academy of Motion Picture Arts and Sciences (AMPAS). The test measured the spectral power distribution of tungsten light reflected off a spectralon target made of barium sulfate using a Photo Research SpectraScan Model 705 spectroradiometer. The results were graphed according to their wavelength (in nanometers) along the X axis, versus radiance (in watts per steradian per meter squared) along the Y axis. In the top graph, the yellow line represents the baseline tungsten light reading reflected off the barium sulfate target. This graph illustrates the excellent filtration properties of both the ProStop IRND (shown in green) and the Firecrest ND (shown in blue). Both filters appear nearly flat from this perspective. The second graph emphasizes the differences between the two filters by removing the baseline tungsten reading and zooming-in on the Y axis. On closer inspection, the graph shows the ProStop IRND strongly attenuating the near-infrared spectrum before returning to neutral attenuation of the infrared spectrum around the 730nm mark. Firecrest (shown in blue) performs perfectly linearly in the visible light spectrum, before completely eliminating the infrared energy at around the 700nm mark. Compared to the ProStop IRND (which is the previous benchmark in IRND filtrations) the performance shown by Firecrest ND is nothing short of revolutionary. Firecrest ND truly is the future of ND filtration for digital sensors. Results in-the-field confirm the test data. The new Firecrest ND is amazingly neutral regardless of the camera make or model used.