The NiSi Cinema 4 x 5.65” Variable Neutral Density 0.3-1.5 (1-5 Stops) Filter is a variable natural density filter with the range of 0.3-1.5 or 1-5 stops. It creates a darkening of the entire image, allowing a cinematographer to shoot with a wider aperture or slower shutter speed. The degree of density is easily controlled by rotating the gear or combining a lens motor to control the density. The aluminum and glass filter is either 6mm or 12mm thick and occupies a single filter slot in a compatible 4 x 5.65″ matte box or can be used without a matte box. It offers 1 to 5 stops of neutral-color light reduction and features NiSi’s optical glass.