Blue-green much larger color gamut than RYB color space. The first recorded use of "cyan" as a color name in English was in 1879. The color turquoise, a representation of the color of the semi-precious stone turquoise. The first recorded use of "turquoise" as a color name in English was in 1573. The color "turquoise" is a light tone of blue-green. Green-blue had been a Crayola color since 1958. It was continued as a Crayola crayon color until 1990. One definition of the color is in the Munsell color system (Munsell 5BG) although there is wide-spread acceptance and knowledge of the
C-41 process not is a subject of some debate. C-41 film consists of an acetate or polyester film base, onto which multiple emulsions are coated. Each layer is only sensitive to a certain color of visible light. In the classic illustrative example, there are three emulsions: one is red sensitive, another is green sensitive, and the top is blue-sensitive. Beneath the blue layer is a yellow filter, composed of dyes or colloidal silver. All silver-based photographic emulsions have some sensitivity to blue light, regardless of what other colors they may be sensitized for. This filter layer serves to remove the blue light,