Color chart

Shirley cards are color reference cards that are used to perform skin-color balance in still photography printing. The industry standard for these cards in North American photography labs in the 1940s and 1950s depicted a solitary "Caucasian" female dressed in brightly colored clothes. Very few of these color reference cards showed an adult male as the reference image.[1] Light skin tones therefore served as the recognized skin ideal standard. Stock color film chemistry for still cameras was designed originally with a positive bias toward "Caucasian" skin tones because of its high level of reflectivity.[1]

By the mid-1990s, Japanese companies redesigned their Shirley cards using data from their own color preference tests. The new reference card featured Japanese women with light yellow skin.[1]

In 1995, Kodak designed a multiracial norm reference card. This card showed three women (Caucasian, Asian, African) with different skin colors and brightly contrasted clothing.[1]

A similar cinematic calibration technique is known as the China Girl.

The ColorChecker, first produced as the "Macbeth ColorChecker" in 1976, is a cardboard-framed arrangement of twenty-four squares of painted samples based on Munsell colors. Its previous maker Gretag–Macbeth was acquired in 2006 by X-Rite.

ColorChecker Color Rendition Chart

A ColorChecker chart can be used to manually adjust color parameters (e.g. color temperature) to achieve a desired color rendition. ColorChecker charts are available in different sizes and forms.

Standardized IT8 charts (also called IT8 targets) are made by several companies including Coloraid.de, FujiFilm, Kodak, LaserSoft Imaging.[2] Unlike ColorChecker charts, IT8 charts are supplied with measurement values and can be used to create ICC color profiles by software (e.g. for digital cameras) to create reproducible color management.

This is an IT8 color target made in EGM Laboratories in Barcelona, Spain. It has a very big gamut, slightly bigger than the ProPhoto color space.

Pier Andrea Saccardo proposed this "chromotaxy scale" in 1894, to standardize the naming of colors of plant specimens.

Pier Andrea Saccardo's chromotaxy scale

Color charts can take custom forms, as for example the calibration target used by the Curiosity rover for its Mars Hand Lens Imager (MAHLI).

Calibration target on the Mars Curiosity rover

The European Pharmacopoeia monograph 2.2.2 is a method to determine the degree of coloration in liquids, applied to pharmacological compounds, drug substances and finished product. It consist in 3 stock solutions, yellow, red, and blue. These are prepared by dissolving in hydrochloride acid ferric chloride, cobalt chloride, or copper sulfate, respectively. The stock solutions are then used in different proportions to prepare five standard solutions, termed B (brown), BY (brownish-yellow), Y (yellow), GY (greenish-yellow), and R (red). Results are given by observation of the test material against the standard solutions, and expressed as less intensely colored as the next color standard (for example, "color of solution colorless to slightly brown-yellow liquid, <BY4").[3] This method has been updated in Ph.Eur. release version 10 to include a digital method that eliminates the errors inherent in visual methods due to differences in human perception, while providing a quantitative color value.