Lightness (sometimes called value or tone) is a property of a color, or a dimension of a color space, that is defined in a way to reflect the subjective brightness perception of a color for humans along a lightness–darkness axis. A color's lightness also corresponds to its amplitude.

Various color models have an explicit term for this property. The Munsell color model uses the term value, while the HSL color model and Lab color space use the term lightness. The HSV model uses the term value a little differently: a color with a low value is nearly black, but one with a high value is the pure, fully saturated color.

In subtractive color (i.e. paints) value changes can be achieved by adding black or white to the color. However, this also reduces saturation. Chiaroscuro and Tenebrism both take advantage of dramatic contrasts of value to heighten drama in art. Artists may also employ shading, subtle manipulation of value.

The Munsell value has long been used as a perceptually uniform lightness scale. A question of interest is the relationship between the Munsell value scale and the relative luminance. Aware of the Weber–Fechner law, Munsell remarked "Should we use a logarithmic curve or curve of squares?" Neither option turned out to be quite correct; scientists eventually converged on a roughly cube-root curve, consistent with the Stevens power law for brightness perception, reflecting the fact that lightness is proportional to the number of nerve impulses per nerve fiber per unit time. The remainder of this section is a chronology of lightness approximations, leading to CIELAB.

Juliette Binoche (French pronunciation: [ʒyljɛt binɔʃ]; born 9 March 1964) is a French actress, artist and dancer. She has appeared in more than 40 feature films, been recipient of numerous international accolades, is a published author and has appeared on stage across the world. Coming from an artistic background, she began taking acting lessons during adolescence. After performing in several stage productions, she was propelled into the world of auteurs Jean-Luc Godard (Hail Mary, 1985), Jacques Doillon (Family Life, 1985) and André Téchiné, who made her a star in France with the leading role in his 1985 drama Rendez-vous. Her sensual performance in her English-language debut The Unbearable Lightness of Being (1988), directed by Philip Kaufman, launched her international career.

She sparked the interest of Steven Spielberg, who offered her several parts including a role in Jurassic Park which she declined, choosing instead to join Krzysztof Kieślowski on the set of Three Colors: Blue (1993), a performance for which she won the Venice Film Festival Award for Best Actress and a César. Three years later Binoche gained further acclaim in Anthony Minghella's The English Patient (1996), for which she was awarded an Academy Award and a BAFTA for Best Supporting Actress in addition to the Best Actress Award at the 1997 Berlin Film Festival. For her performance in Lasse Hallström's romantic comedy Chocolat (2000) Binoche was nominated for an Academy Award for Best Actress.

Portia Lee James DeGeneres (born Amanda Lee Rogers; 31 January 1973), known professionally as Portia de Rossi ( /ˈpɔərʃə də ˈrɒsi/), is an Australian actress, best known for her roles as lawyer Nelle Porter on the television series Ally McBeal and Lindsay Bluth Fünke on the sitcom Arrested Development. She also portrayed Veronica Palmer on the ABC sitcom Better Off Ted and Olivia Lord on Nip/Tuck.

Born Amanda Lee Rogers in Horsham, Victoria, Australia,^{[citation needed]} she is the daughter of Margaret, a medical receptionist, and Barry Rogers. Her father died when she was nine. She was raised in Grovedale, a suburb of Geelong in Victoria, Australia. As a child, she modelled for print and TV commercials. She adopted the name Portia de Rossi at the age of 15, stating in 2005 that she had intended to reinvent herself, using the given name of Portia, a character from William Shakespeare's The Merchant of Venice, and an Italian last name.

Her first significant role was playing a young and impressionable model in the Australian 1994 film Sirens. Soon afterwards she moved to Los Angeles and had guest roles on several TV shows, and a permanent role in Nick Freno: Licensed Teacher, before landing a role in the film Scream 2. During this time in the United States, de Rossi worked diligently to replace her native Australian accent with her current General American one.

Brian Peter George St. John le Baptiste de la Salle Eno (born 15 May 1948), commonly known as Brian Eno or simply as Eno ( /ˈiːnoʊ/^{[citation needed]}), is an English musician, composer, record producer, singer, and visual artist, known as one of the principal innovators of ambient music.

Eno studied at Colchester Institute art school in Essex, England, taking inspiration from minimalist painting. During his time on the art course at the Institute, he also gained experience in playing and making music through teaching sessions held in the adjacent music school.

He joined the band Roxy Music as keyboard and synthesiser player in the early 1970s. Roxy Music's success in the glam rock scene came quickly, but Eno soon tired of touring and of conflicts with lead singer Bryan Ferry.

Eno's solo music has explored more experimental musical styles and ambient music. It has also been extremely influential, pioneering ambient and generative music, innovating production techniques, and emphasising "theory over practice". He also introduced the concept of chance music to popular audiences, partially through collaborations with other musicians.