Product Design Sketching

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Product Design Sketching

• Chromatic Theories

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Color Spectrum

• The range of colors seen by human eye is the
  visible color spectrum

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Color Models

• RGB Model
• Additive model (as that of light)
• The 3 primary colors add up to form the white
  color
• CYMK Model
• Subtractive model (as that of paint pigment)
• Cyan, Yellow, Magenta and Black add up to become
  the black color

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Basic Attributes of a Color

• A color can be denoted by its HSB value, i.e. the
  3 attributes
• Hue
• Tint of the color
• Location of the color in the color spectrum
• Saturation
• Intensity or amount of color pigment
• Brightness / Lightness
• Light value of the color
• Intensity or amount of light

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HSB Values

• You may use the colour picker of Adobe PhotoShop
  to identify the HSB values of your colour pencil

Adjust hue and saturation
Adjust brightness
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Saturation vs. Brightness
brightness
saturation
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Colour Physiology and Psychology

• Our perception of colour is governed not only by
  Physics but also by the biological structure of
  our eyes and the wiring of our brain

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Colour Perception

• The color of an object being seen is determined
  by
• Local color (of the objects surface material)
• Ambient color (of the light source)
• Reflected color (from another objects nearby)

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Color Perception

• What we see is not real but perceived

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Colour Perception

• Dithering is a technique used in computer
  graphics to create the illusion of color depth
  with a limited color palette
• In a dithered image, colors not available in the
  palette are approximated by a diffusion of
  colored pixels from within the available palette.
  The human eye perceives the diffusion as a
  mixture of the colors within it.