These filters allow you to concentrate on the subject itself & eliminate all unnecessary background detail. Use them for portraits, nudes, still life, landscapes, or anytime you want to suppress unwanted background detail & to capture the spirit of the subject. Each of the five Pre-shaped frames comes in two sizes to match different subjects & lenses. Don't use super wide-angle lenses. The smaller the lens aperture (and the further the Pre-shaped frame is from the front of the lens) the sharper the cutout shape. The distance between your lens & the Pre-shaped frames can be varied by using a Cokin Modular Hoods (255) & the Coupling ring (308). Also, the lighter the subject or background itself the more pronounced the edge of the cutout will appear. These frames can be combined with most of the Cokin system filters.