The  PROII CPL-VND 2-in-1 Filter from Haida is a variable neutral density filter that provides an exposure reduction of 3 to 7 stops. The 0.9 to 2.1 optical density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed without overexposing your image. By slowing your exposure time, you can create motion blur for special effects or to convey a sense of movement. Opening your iris allows you to create shallow depth of field, which can help isolate your subject. For easier, repeatable control over density settings, the front ring is also visually demarcated with dots that represent different density values and includes a rotation lever to further enable fast, as well as precise positioning of the front ring.