A phenomenon where multiple different opsins can be expressed within a single type of cone cell. For example, an organism may have genes for - and express - two classes of opsin with different peak wavelength, which would suggest they…

A former blog on colorblindness; run by the maker of the Color Blind Check app.

Usually called Cerebral Achromatopsia. A condition where the eyes are capable of seeing color, but a disorder with the color region of the brain prevents interpretation of color information from the eyes.

A disorder where a subject is unable to name colors, or identify them when given a name. Despite this difficulty with Denotative Color Tasks, they can perform all other Color Tasks with ease. They will pass all modern colorblind tests,…

This app for android consists of a mosaic test for red/green and blue/yellow CVD. This is the preferred self-test of the online colorblind community, as the results show more granularity and uncertainty than competing tests.

A color code can encode information as color (such as Traffic Lights), or can encode color as other information (such as ColorADD or FeelIPA). https://www.youtube.com/watch?v=b_HJavHqCHY

Color constancy is a feature of the human color vision which ensures that the perceived color of objects remains relatively constant under varying illumination conditions. A green apple for instance looks green to us at midday, when the main illumination…

Color Contrast - as opposed to Luminance Contrast - indicates the difference between two - generally Isoluminant - Chromaticities. The ability of an individual to distinguish Chromaticities is defined by their Color Contrast Sensitivity.

An individual's ability to differentiate two similar colors; The more sensitive an individual's color contrast, the more colors they can see. A test to determine Color Contrast Sensitivity presents you with a shape or letter comprising a background and foreground…

When testing for Color Contrast Sensitivity, the point at which the two colors become indistinguishable is the Color Contrast Threshold. When the thresholds are defined on two perpendicular axes, a MacAdam Ellipse can be superimposed on a Chromaticity Diagram to…

Glasses or Lenses that aim to 'enhance' the vision of the colorblind. There are several common manufacturers: EnChromaColorlitePilestoneColorMAXVino Optics https://www.youtube.com/watch?v=WIzaUE0JSRI

The difference between two colors is a quantified metric that describes how similar two colors are. One problem of the CIEXYZ (1931) Color Space is that the color differences are not uniform. This was corrected in the CIELUV (1976) Color…

See Color Space. While they are not completely interchangeable, they are often used as such.

This android app uses your phone's camera to estimate the color of an object. There are some nuances about increases the accuracy of this method, so I made a tutorial in the following video: https://www.youtube.com/watch?v=9WDr4e8eJmc

An abstract mathematical model describing a way colors can be represented numerically. Color models can be based on physics or human perception. Physical descriptions of color can be additive (describes mixing of light, e.g. RGB) or subtractive (describes mixing of…

A trichromatic human with no detectable Color Vision Deficiency. The Standard Observer is generally the reference used for what constitutes Color Normal. Sometimes Normie in the context of Color Vision.

Also CRI; a quantitative measure of the ability of a light source to reveal the colors of objects faithfully in comparison with an Standard Illuminant or ideal light source (e.g. D65). Light sources with a high CRI are desirable in…

Color Space is a property of: Visual System - for example, in humans, the color space of a Dichromat is smaller than the color space of a Trichromat.Display - Color screens such as computers/phones have a trichromatic color space, usually…

A system to classify the different ways people use colors. These classifications were originally defined by Cole (1972). There are 5 ways classes: Comparative - Multiple colors must be compared, such as with mixing paintConnotative - Colors are given an…

The body of knowledge concerning color mixing and color vision. An umbrella term that holds all Color Models.

The proper name for Colorblindness

An abstract organization of color Hues around a circle, which shows the relationships between primary colors, secondary colors, etc.. The Color Wheel is a simplification of a Chromaticity Diagram that removes the Chroma/Saturation dimension, leaving only the Hue dimension. Also…

A proprietary system used to supplement colors with symbols. https://youtu.be/b_HJavHqCHY

This is often considered a misnomer because Colorblind individuals are usually not "blind" to color. The term Color Vision Deficiency is usually preferred, though Colorblind is still used colloquially. See also Daltonism or Dyschromatopsia.

The Colorblind Quiz is a series of questions that Normies will usually ask you upon finding out you are Colorblind. Questions can include: What color is this?What color do you see this as?What about this?Are you really colorblind?So what color…