Saturation: The purity of the color; as white light mixes in, the color becomes less saturated (e.g., "electric blue" vs. "robin’s egg blue").
Brightness: The psychological intensity of a color (e.g., the difference between a dim blue spotlight and an intensely bright blue spotlight).
Color Mixing
Subtractive Mixing: Involves combining pigments with a single light source.
Example: Mixing paints.
Additive Mixing: Involves combining multiple light sources to create new colors.
Subtractive Mixing
Combining Pigments:
Red paint appears red because it reflects red wavelengths and absorbs others.
Each additional pigment absorbed more wavelengths, reducing light reflection.
Process: More pigments added mean more wavelengths absorbed and less reflected, resulting in the removal of light.
Subtractive Color Mixing Visualization
How it works:
Each pigment absorbs specific wavelengths and reflects others, leading to combined effects on color perception.
Additive Mixing
Combining Lights:
Each added light source increases the available wavelengths, enhancing brightness.
The resulting color can often be predicted using the color wheel.
Color Wheel Reference
Color Degrees:
Chartreuse (150°), Green (180°), Yellow (120°), Orange (60°), Red (0°), Magenta (330°), etc.
Metamers
Definition: Pairs of lights that appear identical but consist of different wavelengths.
Example: Yellow can be produced with a single wavelength or by mixing green and orange light in equal amounts.
Applications of Additive Color Mixing
Used in:
Color printing.
TVs and computer monitors.
Stage lighting.
Implications of Additive Color Mixing
Three widely spaced wavelengths can create all visible colors.
Indicates efficiency of color production using limited receptors.
Some colors do not mix (e.g., no true "reddish green").
Mixing can result in white light.
Related theory: Opponent-process theory suggests that certain color pairs are managed by the same underlying mechanisms.
Trichromacy Theory
Proposed by Young in the 1800s: Human beings have three types of color detectors in their eyes, enabling perception of the full color spectrum through additive mixing.
Combined Theories: Trichromatic and Opponent-Process
Cone Receptors: Respond to subsets of the visible spectrum.
Opponent Cells: Respond oppositely to pairs of colors such as blue-yellow and red-green, processing color information in a collaborative manner.
Determinants of Color Perception
Wavelength: The specific wavelength dictates the color seen.
Amount of Light: The intensity of the light affects brightness and visibility of color.
Surrounding Colors: Impact of adjacent colors creating simultaneous color contrast.
Recently Seen Colors: Influence perceptions of color based on previous visual experience (sequential color contrast).
Memory for Typical Colors: Prior knowledge and memories impact how colors are perceived in context.