Additive and subtractive primary colors

RGB color Venn diagram showing how to create any color from only red, blue, and greenThe three primary colors red, green, and blue are called the additive primary colors (RGB). The additive color process occurs in the lamps inside a computer projector or an LED computer or television screen. Each has a collection of tiny lamps—some red, some green, and some blue—that illuminate in relative intensity to create any color in the rainbow. When two adjacent, tiny pixels on your LED screen show blue and red, your eye sees them combined together as magenta. If blue, red, and green all illuminate next to each other, then your eye sees white light. Read the text aloud
Digital images are made up of many individual red, green, and blue pixelsDigital images are made of tiny dots, or pixels, of color; a one megapixel image has one million dots. Each pixel in the image is captured by three tiny sensors in the camera, which, like the human eye, respond to red, green, or blue light. In turn, each sensor records a number from 0 to 255 corresponding to the intensity of the light it receives. A one megapixel digital image is a string of three million numbers that prescribe the intensity of red, green, and blue for each pixel. The maximum is assigned to 255 because computers use binary numbers and 28 = 256. Read the text aloud Show Hexadecimal RGB colors for webpages
Digital (as opposed to analog) information can be stored reliably in computer memory. Digital files, such as images or music, can also be copied quickly, inexpensively, and without information loss; analog information degrades with each subsequent copy. On the other hand, many people have expressed concern about the security of digital personal information, the theft of copyrighted material, and the ease of accidental deletion.
How are the colors of the ink on a book page different from the colors on a TV screen? You see the light on the page reflected from the Sun or a light bulb. When printed, the red color on this page was created by a combination of pigments that reflect only magenta and yellow but absorb all the other colors within the white light shining on it. Read the text aloud
Subtractive primary color diagramPrinted illustrations use cyan, magenta, and yellow pigments in the ink to create any possible color. Professional printers realized that they could not obtain dark blacks with only cyan, magenta, and yellow, so they added a fourth ink—black or “K.” Cyan, magenta, yellow, and black (K) are known as subtractive primary colors (CMYK). This is called a subtractive primary color process because the pigments remove the light upon reflection, rather than being sources that emit light. Read the text aloud
How is additive primary color mixing different from mixing colors with paint? Show

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