Steel frame with stretched fabric for large-scale light diffusion or negative fill. Standard 12×12 ft, 25–35 kg, compatible with various nets and silks.
Technical Details
Standard butterfly frames are made of 38-48 mm steel tubing with a total weight of 25-35 kg without fabric. The frame construction features 8-12 tension points for even fabric distribution and reinforcing cross braces for wind stability. Common fabrics include 1/4, 1/2, and full stop nets for precise light reduction, silk (white or bleached) for soft diffusion, and solid black for complete blackout. Modern versions increasingly use carbon composite frames, which weigh 40% less while offering identical stability.
History & Development
Matthews Studio Equipment introduced the first standardized 12x12 butterfly frame in 1952, inspired by the improvised large diffusers of the 1940s at MGM and Warner Bros. The breakthrough came in 1961 with the introduction of modular tensioning mechanisms by Mole-Richardson, which reduced fabric changes from 20 to 5 minutes. From 1995, foldable versions became established for location shoots, while since 2010, hexagonal 4-meter variants have been developed for 360° shots and LED walls.
Practical Use in Film
Roger Deakins used six 12x12 butterflies with 1/4 nets in "Blade Runner 2049" (2017) for consistent daylight diffusion in city scenes. For exterior shots, butterflies are typically positioned 3-5 meters above actors as an overhead silk, eliminating harsh sun shadows without distorting the light direction. Setup requires at least three grips and takes 15-20 minutes, but offers unmatched flexibility in large-area lighting without visible fabric edges in wide-angle shots.
Comparison & Alternatives
Compared to 6x6 frames (silk), butterflies double the covered area, while 20x20 overheads require triple setup time and permanent crane positioning. LED soft panels like the ARRI SkyPanel S360-C are increasingly replacing butterfly-silk combinations, but do not achieve their natural light quality in mixed lighting situations. For VFX-intensive productions, butterflies are often replaced by chroma key-capable LED volumes, which simultaneously provide a light source and digital background.