Nisi IRND 4x5.65 Filter Set (ND 0.6, 0.9, 2.1)
ND filter is short for neutral density filter. It’s a filter that can reduce and modify the intensity of all wavelengths or color of light equally. The function of the this filter is to reduce the visible light at equal proportion, and won’t change the brightness and color contrast of the scene. IR ND is based on the common ND filter of adding resistance to infrared light function, IR is short for “Infrared Ray”. NiSi IR ND using H-K9L high quality optical glass as material, with double-sided nano-coating, to reduce the intensity of visible light entering the lens, would not change the brightness contrast of the scene, but also effective inhibition of ultraviolet and infrared light through.