The Iris Expansion filter set includes an ND64 (6-stop), ND128 (7-stop), and ND256 (8-stop). We designed this expansion set for Iris users who film in bright, outdoor lighting. Typically, these filter densities will be needed to get shutter speed to 1/50th with an ISO of 100 on iPhone cameras. Each filter has 8 layers of coatings on each side to reduce ghosting and severe flaring, all on top of our production-grade Cinema Series glass. These filters retain outstanding color neutrality and sharpness for film-makers obsessive over image quality.