Correction for the film and television industries.
The Rosco Gels Cinegel range includes over 75 tools for controlling light. Since it's introduction in 1970, Cinegel has continually developed and grown to meet the working needs of the professional. In 1974, Cinegel won an Academy Award for technical achievement.
(Rosco Cinegel, GAM Filter)
Like surface coated PET, deep dyed film begins with a
roll of clear polyester. The film is passed through a bath
of heated solvent suffused with dye. The solvent causes
the PET film to swell expanding the polymer structure
of the film and allowing the dye molecules to penetrate
the surface. The film is then washed and the polymer
contracts to its normal form, trapping the dye molecules
below the surface. Compared to surface coating, more
extreme temperatures are required to cause the dye particles to sublimate through the surface. Deep-dyed filters are,
therefore, more resistant to fading than surface coated.