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16 color 1

  1. 1. Visual Imagination
  2. 2. It is now an accepted fact that color is truly in the eye of the beholder. "This is due to the fact that, as sensed by man, color is a sensation and not a substance." Joseph Friedman - History of Color Photography
  3. 3. In 1704 Isaac Newton first passed a beam of white light through a prism, and saw it divide into multiple and varied color bands. He defined it as the spectrum.
  4. 4. Sunlight Prism A Shade Inversely, he determined that, combining all color bands together produces pure white light or sunlight. Newton thought that light was a stream of tiny particles. In 1801, Thomas Young conducted an experiment that provided evidence that visible light has wave-like properties.
  5. 5. Light waves are reflected or absorbed by surfaces of objects around us. The reflective characteristics of a surface allow us to interpret certain light-wave qualities as particular colors. Hence the theory: color is a property of light.
  6. 6. To understand color it is, therefore, necessary to have some understanding of light.
  7. 7. What is Light? Light is a form of radiant energy that consists of separate bits of energy particles called photons that behave in a uniform wave pattern.
  8. 8. Light is just the small, portion of the larger electromagnetic continuum (spectrum) that is visible by the naked eye. ELECTROMAGNETIC SPECTRUM 10-14 meters 106 meters Cosmic Gamma X-rays UV Rays Rays Light InfraRed Microwaves TV VISIBLE SPECTRUM 400 500 600 Wavelength (nm) 700 Radio
  9. 9. The region of visible light falls between the ultraviolet and infrared regions. ELECTROMAGNETIC SPECTRUM 10-14 meters 106 meters Cosmic Gamma X-rays UV Rays Rays Light InfraRed Microwaves TV VISIBLE SPECTRUM 400 500 600 Wavelength (nm) 700 Radio
  10. 10. Light waves are measured in nanometers (nm) which are equal to 1 billionth of a meter (1 nm = 10-6 meter). . ELECTROMAGNETIC SPECTRUM 10-14 meters 106 meters Cosmic Gamma X-rays UV Rays Rays Light InfraRed Microwaves TV Radio VISIBLE SPECTRUM 400 500 600 700 Wavelength (nm) Light, then, is electromagnetic energy whose wave-length is measured between 400 nm and 700 nm.
  11. 11. The size of the wave (wavelength and amplitude) determines the color of light
  12. 12. Although some colors can be created by a single, pure wavelength, most colors are the result of a mixture of wavelengths. A French organization, the Commission International de L'Eclairage (CIE), developed a method for systematically measuring color in relation to the wavelengths they contain. This system became known as the CIE color model (or system).
  13. 13. The model was originally developed based on the tristimulus theory of color perception. The theory is based on the fact that our eyes contain three different types of color receptors called cones. These three receptors respond differently to different wavelengths of visible light. This differential response of the three cones is measured in three variables X, Y, and Z I n the CIE color model. This gives a 3-D model which is then projected onto one plane to give a 2-D graphic. X Y and Z are mapped to X and Y coordinates
  14. 14. The spectral energy locus, shows the distribution of light wavelengths in terms of nanoseconds, clearly separating the visible spectrum into 3 principal ranges. At the extreme ends of these ranges are the three principal colors or hues of light. RED BLUE GREEN
  15. 15. What is Color? COLOR is a phenomenon of perception not an objective component or characteristic of a substance. Color is an aspect of vision; it is a psychophysical response consisting of the physical reaction of the eye and the automatic interpretive response of the brain to wavelength characteristics of light above a certain level of brightness.
  16. 16. Three factors must be present for color to be perceived: light, the object light strikes, and the observer who perceives this event.
  17. 17. When we talk about the color of an object, we usually refer to the wavelength that object reflects when struck by natural light. • Wavelengths of light reflected or absorbed by object determine the color we perceive an object to be. • Only reflected wavelengths reach our eye and are seen as color • chemicals that are capable of selectively reflecting one or more frequencies of white light are known as a pigments.
  18. 18. We will return to light theory a little later on, but for now, our concern will be with the mixture of pigments rather than the mixture of various light frequencies.
  19. 19. What is Pigment ? Pigment is the surface property of of a material that allows it to absorb and reflect specific light frequencies. Pigments are also natural or synthetic agents that constitute the color in paint.
  20. 20. The mixing of pigment colors yields additional color combinations similar to that observed in light . Pigment color mixing is termed subtractive color mixing. It is so termed because the resulting colors are somewhat duller than the primaries, revealing less reflective properties, or less color “brightness.”
  21. 21. Pigment color theory is based on the three primary colors of pigment: red blue and yellow. These three colors are pigment equivalents of the spectral red, blue and yellow. They are so termed primary because they cannot be produced by the mixture of any other colors.
  22. 22. Although color theories existed since Aristotle’s time, the 18th century generated a great deal of interest in color relative to both light and pigment. The renowned philosopher, poet and scientist Wolfgang von Goethe constructed the first practical color wheel which was comprised of six spectral colors evenly distributed around a circle. Goethe color wheel
  23. 23. In the same century, Herbert Ives expanded on Goethe’s color wheel and devised a model which showed that a full range of spectral hues can be obtained through the admixtures of the three primary hues and the secondaries they form. Ives color wheel
  24. 24. Albert H. Munsell, a late 19th and early 20th century painter, developed a system of color notation that is used up to this day as one of the color standards used by the US National Bureau of Standards. Munsell’s 3-D color “tree”, is one of the most thorough analyses of color to this date. It is, however, based on the 12 hue color wheel developed by Ives.
  25. 25. The three primary colors in pigment are: RED, BLUE AND YELLOW
  26. 26. When the three primaries are combined or mixed they form the three secondaries: GREEN, ORANGE AND VIOLET
  27. 27. When primaries are mixed with adjacent secondaries, intermediates are formed.
  28. 28. When secondary colors are mixed they form tertiaries. Orange/Green Orange/Violet Green/Violet Tertiary colors do not exist on the color wheel.
  29. 29. When a primary is mixed with a non- adjacent secondary it forms a neutral. Neutral colors do not exist on the color wheel. Neutral colors are comprised of various quantities of all three primaries
  30. 30. Secondaries opposite the primaries on the Ives color wheel are called complements. Any two colors opposite each other on the color wheel are also called complements.
  31. 31. Complementary colors intensify the effect of each other. This effect is called simultaneous contrast.
  32. 32. When a color is placed against a gray background, the background appears as a dull version of the color’s complement.
  33. 33. Remember, the only pure colors are spectral colors (those present in light) all pigment colors are, in some way,effected by the surface they are observed from.
  34. 34. THE CHARACTERISTICS OF COLOR Non-colors that affect color quality. IN THEORY WHITE: In pigment – the absence of color BLACK: In pigment – the sum of all color BLACK GRAY: Any mixture of gray and white
  35. 35. HUE – A pure color, containing no other color, black, white or gray. TINT – A hue with white added SHADE - A hue with black added. TONE - A hue with black and white gray added
  36. 36. VALUE – The relative lightness or darkness of a color. Values can be altered by adding white or black to a color. CHROMATIC VALUE SCALE
  37. 37. Value: Light and dark values are low in intensity. Middle values are highest in intensity.
  38. 38. SATURATION – The density of same color pigment properties. High medium and low saturation High saturation Low saturation
  39. 39. CHROMA - The degree of purity in a color. Higher in Chroma Lower in Chroma High Chroma Low Chroma
  40. 40. INTENSITY – The relative brightness or brilliance of a color, resulting from the degree of saturation or chroma.
  41. 41. Light Color Theory: A slight review: Observing light, as observing pigment seems to hardly require a theory of any kind. It is when we attempt to use light and pigment, in some creative or constructive way, that we look for an explanation regarding the nature and behavior of these phenomena. In pigment, a practical model for mixing colors was created by the color wheel. Is this possible in light theory?
  42. 42. Light is a form of radiant energy that is just a small part of the larger electromagnetic continuum that is perceivable by the naked eye. Visible light falls between the infrared and ultraviolet regions. 400 450 500 550 600 650 700 Wavelength (nm.) Problem Redness at the shortest and longest wavelengths
  43. 43. Fortunately, through experiments performed to observe and measure what people see, an explanation does exist. Human color sensitivity was mapped into a perceptually uniform color space known as CIELAB. (We have seen this previously.) Since the human eye forms a natural continuity in color vision, and is not Interrupted in any way by the discrepancy of if IR and UV frequencies, a color band or “wheel” can be formed to create a practical relationship between the hues.
  44. 44. By placing the spectral colors in a circle, we can observe a curious relationship. The frequency between a certain green (500 nm) and red (700 nm.) is a yellow (600 nm. - called amber) Similarly, the frequency between green (500 nm.) and blue (470 nm.) was Identified as cyan (485 nm.) Since the visible spectrum extends from ultra-violet to Infra red, that “purple” range of the spectrum is combined To form “non spectral” hues. YELLOW CHARTREUSE ORANGE 580 550 GREEN 500 620 700 Spectral Hues RED Nonspectral Hues 485 CYAN 400 470 BLUE PURPLE
  45. 45. Light Color Theory As previously mentioned, in light, there are also three primary colors: red, blue and green. They Are termed primary because their admixture, in different values and intensities, will yield the remaining colors in the visible spectrum.
  46. 46. Additionally, when the primary colors are individually introduced (from separate light sources), and are superimposed on each other, on a neutral surface they produce white light. Mixing colors in this way is termed additive color mixing.
  47. 47. Additive color mixing is so termed, because new colors are formed as new light frequencies are added to each other. For example: when a red color frequency is superimposed on a green one, a yellow (Amber) frequency emerges. The secondary colors Of light are: amber magenta and cyan.
  48. 48. There is also subtractive color mixing in light. This is achieved by superimposing color filters on each other within a single source of light. In the theatre these filters are called gels. When superimposed, filters block each other’s frequencies until all light is absent. To remove all traces of light it is best to use secondary color filters Namely : amber.
  49. 49. The Effect of Color Filters on Color and Light Transmission
  50. 50. Introducing individual color frequencies to colored surfaces Also results in subtractive color mixing.
  51. 51. A clown under natural lighting (all light frequencies).
  52. 52. Green Cyan Green – allows mostly green and amber wavelengths. Cyan - allows no reds Amber – allows no blues or violets Red – allows nothing but red Amber Red
  53. 53. Much of the terminology used in Pigment Color Theory does not apply to Light Color Theory. Terms such as Value, Saturation, Chroma are typically not Employed.
  54. 54. Here are some terms to remember: INTENSITY - the amount of light being transmitted HUE - Color WHITE (in light) – The sum of all color frequencies. BLACK (in light) – The absence of light. WARM and COOL color ranges also exist in light But are slightly different from their pigment counterparts.