Lightweight foam board sandwiched between two cardboard layers — used as a reflector, flag, or light shaper on set.
Technical Details
Commercially available foam core boards consist of a 5 mm thick polystyrene core with a 0.2 mm paper facing. The white surface reflects 85-90% of incident light with a reflection angle of nearly 180°, creating soft, diffuse light. Black variants absorb 95% of the light. Professional versions feature a matte vinyl coating that is more scratch-resistant than paper. The weight is approximately 280g per square meter.
History & Development
Foam core was developed in 1957 by the Monsanto company for architectural models and first found professional film application in 1972 through gaffer Joe Dunton on the set of "Cabaret." The breakthrough came in 1975 with "Jaws," where the boards were used as a cost-effective alternative to heavy plywood reflectors. Since the 1980s, they have been standard equipment in every lighting department.
Practical Use in Film
On "Blade Runner" (1982), Jordan Cronenweth used hundreds of foam core boards to create the replicants' characteristic rim light. The boards are typically positioned with C-stands and super clamps or held by assistants as handheld reflectors. Especially in close-ups, they fill shadows on the face without creating hard edges. For exterior shots, they serve as bounces for sunlight or HMI lights.
Comparison & Alternatives
Unlike silver reflectors, foam core boards do not create hotspots and are cheaper than professional textile reflectors (Flexfill). LEDs have partially replaced them as fill lights, but do not offer the same natural light quality. Modern alternatives include foldable reflectors with a white gold coating or digitally controllable LED mats, which however cost 10-20 times as much.