The 100x150mm Nano IR Hard Graduated Neutral Density filter from Nisi is specially designed for landscape photographers. This filter is made from high quality optical glass (not rasin) with nano coating to prevent losing any single bit of detail. Neutral density filters do not affect the coloration of the image and the 0.6 density provides a 2 stop reduction in light from entering the lens. This filter measures 3.9 x 5.9″ / 100 x 150mm and is compatible with the Nisi 100mm filter holder or other 100mm Standard Filter Holder (Lee, Cokin or Formatt Hitech). The filter can be repositioned in the holder allowing recompose the photo for the best result.
The use of Hard GNDs is usually defined by a obvious boundary between the bright and dark area of the scene. They are therefore used when the separation between the bright and the dark areas of the scene is very defined, such as the horizon line or the boundary between sea level and the sky.
By using neutral density filter the camera is vulnerable to infrared light which will cast the unwanted red color to the photos when shotting at small aperture. Nisi added the infrared protection coating layer to this filter which help to eliminate the infrared light through the lens to bring back the nature color.