Enables slow shutter speeds to be used for high speed films, to record movement in subjects such as waterfalls, clouds, or cars

Decreases depth of field by allowing wider apertures to be used, which helps separate subjects from their background

Decreases the effective ISO of high speed film (above ISO 400) and allow it to be used outdoors in bright situations

To allow cine and video cameras (which have fixed shutter speeds) to film subjects such as snow, sand or other bright scenes which could cause overexposure