Full Spectrum Performance.
The color cast seen in most neutral density filters on the market can be seen on a spectral graph as deviations from a flat curve - usually a color cast that results in an increase in transmission throughout the visible spectrum. The X4 ND has the flattest transmission curve throughout the visible range and well into infrared, leading to a more color neutral performance.
And thanks to years of research and development, the X4 ND is incredibly precise to the ideal optical densities. An optimal 10-Stop (3.0) ND filter has a light transmission of 0.1%. With an average light transmission of 0.108% across the both visible and infrared spectrums, the X4 ND hits the mark with great accuracy giving you a more dependable baseline to set up shots.