Barndoors attach to the front of a light and are used to restrict light from areas of a set. Arri barndoors are heat resistant and rotatable. Barndoors narrow the beam spread of a light fixture. They help create a 3-dimensional look to a lighting scheme by placing light in a specific area, or by keeping it away. The more leaves a barndoor set has, or the longer the leaves, the more precisely the beam of light can be controlled.