cinematography Cinematography () is the art of motion picture (and more recently, electronic video camera) photography. Cinematographers use a lens (optics), lens to focus reflected light from objects into a real image that is transferred to some image sen ...

, butterflies (also known as overheads) are large structures with a thin layer of a translucent material, such as cloth, that are placed over a scene to block the glare of direct sunlight. They can control the level of a sunlight in a scene. Allowing consistent shadows over a full day of filming or to make day seem cloudy when it is not. They also protect actors from direct sun. Materials commonly used on butterflies include:

flags A flag is a piece of fabric (most often rectangular) with distinctive colours and design. It is used as a symbol, a signalling device, or for decoration. The term ''flag'' is also used to refer to the graphic design employed, and flags have ...

(black, opaque materials), nets (layers of neutral-colored bobinette), and

diffusion Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in Gibbs free energy or chemical p ...

s (translucent white materials of different densities) for the purposes of blocking, dimming, and scattering light respectively. In general, butterflies are used only for very large materials (6 ft x 6 ft or greater), while smaller sizes are usually sewn onto portable frames (similar in construction to picture frames) for ease of placement and storage.

Use in industry

In industry, butterflies are often called for by their dimensions, which are standard: 6 ft. x 6 ft, 8x8, 12x12, and 20x20. The materials themselves tend to be created at smaller sizes—usually about 8 inches less in each dimension—so as order to ensure a flat, stretched surface when mounted on the butterfly. While portable frames usually consist of light-blocking and scattering materials (flags, nets, and diffusions), butterflies may also be rigged with reflective materials such as silver lame for redirecting light.

References

* {{DEFAULTSORT:Butterfly (Lighting) Film and video terminology