1. Trichromacy
    • Additive color mixing
    • Subtractive color mixing
  2. Pointilism
    • The use of primary color dots to generate other colors
    • Printers
    • Old t.v.'s
  3. Additive color mixing deals primarily with;
    shining two lights together
  4. Subtractive Color mixing primarily deals with;
    • mixing paints
    • photography
    • printing for dye
  5. Subtractive color mixing - Blue + Green=
    • White light
    • Wave lengths are subtracted; only some shine through
  6. Yerllow =
    medium wavelength
  7. Color Space
    a 3-d space that describes all colors (paint swatches)
  8. Three dimensions of color
    • Hue
    • Saturation
    • Brightness
  9. Hue
    Our perception of color; related to the wavelength present
  10. Saturation
    Amount of particular wavelength present; how pure the color is
  11. Brightness
    How intense the color is
  12. Psychological Dimensions -> Physical Dimensions:
    Hue ->
    Brightness ->
    Saturation ->
    • Hue -- Wave length
    • Brightness -- Intensity
    • Saturation -- Purity
  13. Opponent Processes
    Color processing in the LGN
  14. Three types of opponent processing
  15. After Images
    A visual image seen after a stimulus has been removed
  16. Positive after image
    image has same colors as object
  17. Negative after images
    image has reversed or complementary colors
  18. Complementary colors
    • 2 colors that when mixed together make gray/white
    • Colors that are directly across from each other on color circle
    • Spontaneous firing has to balance out/cancel out when looking at blank screen
  19. Supersaturated after images
    small blue square - big yellow rectangle = see blue box in middle
  20. Does everyone see color the same way?
    • General agreement on colors
    • Some variation due to age (lens turns yellow)
  21. Does everyone see color the same way?
    • About 8% of male population are color blind
    • 0.5% of women population have some sort of color deficiency
    • Color deficits are more common in men because genes coding for retinal cones are located on X chromosome
  22. Disorders of color perception
    • Anomolous trichromatism
    • Dichromatism
    • Rod monochromat
    • Cone monochromat
    • Cerebral achromatopsid (damage to cerebrum)
  23. Normal human color vision is called-
  24. Anomolous Trichromatism
    • People have three cones, they just have fewer of one type of photopigment than they should
    • Most common type of color blindness
  25. Protoanomoly
    Have less red cone pigment
  26. Deuteranomally
    Have less green cone pigment
  27. Tritanomy
    Have less blue pigment
  28. Dichromatism
    • Have only 2 types of cones
    • Deuteranopia
    • Protoanopia
    • Tritanopia
  29. Deuteranopia
    lack green cone pigment (missing the whole set of cones, not just a weakness)
  30. Protoanopia
    lack red cone pigment
  31. Tritanopia
    • lack blue cone pigment (looks most distorted)
    • spectrum goes from green to red
  32. Rod monocromat
    • no cones only rods
    • cant see in the dark
    • only see black and white
  33. Cortical Color Blindness =
    • Cerebral achromatopsia
    • Problems with cells coding color in cortex
    • Cones in retina are fine
  34. Unilateral Achromatopsia
    • Blindness in one side
    • 1/2 color, 1/2 black and white (V4)
  35. Does everyone see color the same way?
    • Various cultures describe color differently
    • *Quality of overhead light has a lot to do with how we see color
  36. Color Constancy
    • Daylight/Florescent light
    • The color of an object stays constant despite changes in the wavelength of light illuminating it.
    • Strange because the object is reflecting different wavelengths. But we dont perceive a change in color
    • To acheive color constancy, our visual system takes into account the background illuminations
  37. Memory color
    Familiarity and past experience affect our perception ofcolor
  38. Memory Color Experiment
    illuminate green felt objects with red lights
  39. Nocturnal animals are;
    • colorblind
    • except owls
  40. Many birds have ________ systems; pidgeons have ______
    • 3 cone
    • 6 cone types
  41. Bees and butterflies have;
    ultraviolet color system
  42. Manti shrimp have at least ____ different types of cones
  43. Primates have;
    3 cones
  44. Other mammels (dogs, horses, etc) have only ____ cones.
  45. Cats are best categorized as;
    anomolous trichromatis
  46. Binocular depth cue
    depth cue that relies on info from both eyes
  47. Metrical depth
  48. Nonmetrical depth
    depth cue that provides information about relative depth
  49. Occlusion
    Cue to relative depth in which one object distracts the view of part of another object
Card Set
Perception of Color