The hitech 100mm standard neutral density 06 filter is a professional quality 2 stop 4x nd filter hitech neutral density filters extend the control of exposure parameters and are used in both colour and black white photography to reduce the intensity of visible light they are extremely useful in pictorial photography when shooting maximum apertures in bright light since nd filters uniformly reduce light of all wavelengths there is no effect on the colour rendition these 100x100mm filte