A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

K - Abbreviation for Kelvin.

K14 - The chemical process for developing Kodachrome slides.

Kelvin - The temperature of a light source is given in degrees Kelvin (actually, a temperature reckoned from absolute zero). Daylight, which can vary greatly in the course of a day, is usually estimated at about 6000 degrees Kelvin, which is also the temperature given off by quartz flash-tubes. However, this will produce a far too cold, bluish light to work well with film. Most of the  lamp heads have a glass cover that lowers the temperature to one that is more compatible with film. The uncoated glass cover lowers the temperature to 5800 degrees Kelvin; the UV-coated glass cover-which is standard-lowers it to 5500 degrees (which produces a more attractive skin-tone on film); and the extra UV-coated version lowers the temperature to 5200 degrees Kelvin.

NOTE: The temperature of a flash-tube diminishes successively with the age, in terms of tube usage. The more it is used, the more quickly the change becomes noticeable.

Key light - Also called "main light." The principal source of light on a subject or a scene, usually in reference to a studio light. The key light is generally the brightest light on the subject, or the one that will have the greatest overall effect on the image.

Keystoning - Distortion of a projected image when the projector is not directed perpendicular to the screen.

Kicker - (1) A side or back light often near lens height used to rim faces and model profile shots. (2) A light used to provide an additional highlight or accent on a subject.

Kodak neutral test card - Also known as the “Grey card,” a Kodak neutral test card is an 8" X 10" (20 cm by 25.5 cm) card, about 1/8" thick, that is uniformly grey on one side. The gray side reflects precisely 18% of the white light that strikes it (corresponding to the calibration of a reflected-light meter). It is uniformly white on the other side, which reflects 90% of the light.