Where:
WAVELENGTH: a physical phenomenon

COLOR: a visual phenomenon

Nature of Sight
	Physiology of the Eye

Theory of human sight
	Seems to be:

Cones and rods
	Cones:  B/W vision
		predominantly outside the fovia
		excellent at detecting movement but not detail.
		More sensitive than rods
	Rods:  Color vision
		Predominantly in the fovia
		Excellent at color and outline
		Less sensitive than cones

Precise vision only in the center of the eye.
Peripheral vision catches movement well.  

We must look straight at it to see it clearly.  
In dim light we see no color, and can't see well straight ahead.

SEEING COLOR.
Takes place in BOTH eye and brain.

Three color theory (Young-Helmholtz)
	Red, Blue, Green receptors.  These are the primaries, and 
		perception of all color made by proportional 
		stimulation of these.

Plus the brain: we often see what we expect.

Given that color exists mostly in the way we perceive wavelengths:

COLOR TERMS:

HUE:  Color name.
VALUE/BRIGHTNESS:  How much black or white.
SATURATION/CHROMA:  How pure the color, how much of compliment.

Additive vs. Subtracting mixing:
Subtractive mixing:  pigments reflect only some colors; other colors 
subtracted out.
	Mix two pigments and the result is what is in common.  
	Mix all pigments and the result is black.

Additive mixing:  shine different colored lights on an object and 
the color perceived is the additive mixture of the colors.  
	Basically two colors create a third by
	triggering same receptors as the color they seem to be.

Adding colors moves towards white.  
Subtracting colors moves towards black.

Primaries Additive:  Red, Blue, Green

Primaries Subtractive:Red, Blue, Yellow

BOTH systems are used in stage lighting.

OPTICAL COLOR SYSTEM, a Unified Approach

- Colored light created by subtracting color from white light 
	with color media.
- Colored lights add on stage to create a color mix of two or more.
- The costumes and scenery subtract what they don't reflect.

Audience perceives what is left.

IF A COLOR IS NOT IN LIGHT -OR- IN OBJECT BEING LIT, 
COLOR WON'T BE SEEN BY AUDIENCE!

PERCEIVED COLOR = 
     COLOR INCLUDED IN LIGHT - COLOR DEDUCTED BY PIGMENT	

Color perception psychological AND physical.
Different colors mean different things to different people.

Field/ground effect.

Visual fatigue and brain's tendancy to see "white" light.

One more factor: color of the light source itself.


COLOR TEMPURATURE: the temp that a theoretical "black body" would be 
raised to to incandesce at a particular color.  

Imagine a lump of black iron.  
Start at absolute zero, and begin heating it.  
At some point it will begin to glow, first dark red, then orange, 
	yellow, blue-white, blue, and violet. 
The temperature of the body at particular colors called 
	Color Temperature, 
	measured from 0 K, measured in degrees Kelvin.

Candle-light:  1800 degrees K
Standard lamps:  2600 to 3000 degrees K
T-H lamps:  3200 to 3600
Sunlight:  6000 
Fluorescent:  5600

Intensity:  How much light is there, how bright is the light.  
Controlled by:
	Brightness of the sources
	Number of sources on a scene
	How high they are being run
	Color of sources
		Color filters absorb some of the light
	Color of objects being lit
		You only see reflected light.