Rosco 132

Overview

Rosco 132 is the material or filter number for "1/4 Hamburg Frost", a diffusion filter manufactured by Rosco. It is not a color filter but belongs to the group of diffusion or scattering gels and is used exclusively to scatter light and soften beam edges without altering the source's color temperature.

The number 132 is used by Rosco within the Roscolux and Supergel product lines, denoting the same diffusion characteristic in both. Within the "Hamburg Frost" family, 132 is the lightest grade; stronger variants are 119 (Light Hamburg Frost) and 114 (Hamburg Frost). Rosco explicitly refers to these three filters as a related family (R114, R119, R132).

Effect

The Hamburg Frost gels have an embossed surface texture. This refracts light in such a way that the hard beam edge of a lighting instrument is broken up and softened, while the beam shape and relative brightness are largely preserved. Unlike heavy white diffusion, the gel produces little stray light and flare.

As a "Quarter" grade, the effect of 132 is very subtle: it merely takes the sharpness off the edge without noticeably widening the beam or causing a perceptible loss of intensity. This makes it a tool for fine adjustments when only a hint of softness is desired.

On-Set Use

• Slight softening of hard beam edges from lighting instruments and spots without visibly widening the beam.
• Preferred for long throws (e.g., followspots) and front-of-house positions in stage applications.
• Subtle diffusion when stronger Frost grades (119 or 114) would already spread the beam too much.

Formats

Like other Rosco filters, 132 is available as a sheet in the 20" × 24" size and as a roll (approx. 24" × 25 ft); depending on the product line, it is also available in other special formats (e.g., as sleeves for fluorescent tubes). The filter material is manufactured on a heat-stable, flame-retardant polycarbonate base.