Colors
Similar colors may vary between different companies' formulations - for example, many have a color named "bastard amber", but the transmitted color spectrum may be different. For this reason, gel colors are not referred to by name. Using nature’s color spectrum as a guide, Apollo Design Technology uses a four digit number to designate and locate specific color transmissions: Visible Spectrum. Some manufacturers use a code consisting of a letter and number combination. For example, G841 is a dark blue made by Great American Market (GAM), and R02 is a light amber made by Rosco and L216 is a diffusion filter made by Lee Filters.
Manufacturers produce swatch books, which contain a small piece of each color available, adjacent to its color code, to simplify ordering. Swatch books enable designers and technicians to have a true representation of the manufacturers' range of color.
Most designers choose a limited color palette for generic applications because it is financially and logistically difficult to have access to all colors for a single show.
There are also gels for color correction, such as CTB and CTO, "Color Temperature Blue", and "Color Temperature Orange" respectively. Color correction gels alter or "correct" the color temperature of a light to more closely match the color temperature of a film negative or the white balance of a digital imager. Specifically CTB, which is blue in appearance, will correct tungsten lights that typically have a color temperature in the range of 3,200 kelvins to 5,700 kelvins to more closely match the color temperature of "Daylight" negative, which is usually around 5,400 kelvins (nominal daylight). CTO, which is orange in appearance, will correct a "Daylight" balanced light source (such as many common HMI bulbs) to match the color temperature of Tungsten negative, which is typically 3,200 kelvins. There are "half" and "quarter" variations of the common color correction gels. It is common to use color correction gels for artistic purposes and not just for negative-to-lightsource correction.
Most ranges of gels also include non-colored media, such as a variety of diffusion and directional "silk" materials to produce special lighting effects. "Opal" for example is an opalescent or translucent diffusion filter.
It is common for a gel manufacturer to publish the transmission coefficient or even the spectral transmittance curve in the swatch book and catalogs. A low transmittance gel will produce relatively little light on stage, but will cast a much more vivid color than a high transmission gel, because the colorfulness of a light source is directly related to narrowness of its spectral linewidth. Conversely, the flatter its curve becomes, the closer the gel is to a neutral density filter.
Read more about this topic: Color Gel
Famous quotes containing the word colors:
“Our frigate takes fire,
The other asks if we demand quarter?
If our colors are struck and the fighting done?
Now I laugh content for I hear the voice of my little captain,
We have not struck, he composedly cries, we have just begun our part of the fighting.”
—Walt Whitman (1819–1892)
“All our Concord waters have two colors at least; one when viewed at a distance, and another, more proper, close at hand.... Walden is blue at one time and green at another, even from the same point of view. Lying between the earth and the heavens, it partakes of the color of both.”
—Henry David Thoreau (1817–1862)
“The light is there, and colors surround us. However, if there were no light nor colors in our own eye, we wouldn’t perceive such things outside of us.”
—Johann Wolfgang Von Goethe (1749–1832)