helpful and reader-friendly colour theory tuts
Oximoron alert! Beyond the basics, there's very little written that is reader-friendly about color. Same goes for light, and the history of agriculture.
Basic primer (most of which you probably know):
Hue - The range from red on through the rainbow to red again and percieved color's position on the color wheel
Value - The range from light to dark and the percieved color's position in that range.
Saturation - The distance to gray and the percieved color's position in that range.
Intensity or Contrast - the percieved color's vibrance based on the above values and the relationship of the percieved color to those around it.
Types of colors on the wheel (based on pigment) :
Primary - RYB
These colors are often seen as bold and are often used more for advertisements or other attention-getters, red in particular
Secondary - mixed from two primaries
These colors are attractive but less saturated, they are often used more for landscapes and still lifes.
Tertiariy - mixed from a primary and a secondary
These are mostly delicate colors that can be very beautiful. Most painting is done useing these tones to give life and depth.
Types of mixtures (some varience here) :
Hue - The pure pigment
Tone - A mixture of two pigments
Tint - A mixture of either a hue or a tone with a white or near-white
Shade - A mixture of either a hue or a tone with black or near-black
Cast - A mixture of either a hue or tone with both white and black
False-Black - A mixture of two complementary hues or tones, it can appear black, but contains no black pigment.
Achromatic - Devoid of colors not native to the chosen whites, blacks, and paper or canvas tone.
Monochromatic - Devoid of colors save for the above and a chosen color pigment.
Polychromatic - Breaking any of the above rules.
Complements - Opposite on the color wheel.
Complements used in separate articles will lend percieved saturation to each other. Complements used within the same article will remove percieved saturation from each other. Mixing the two pigments will darken the coor which is more prominent, or - if present in equal amounts, will create a false black, or - if white was present in either color - create gray.
Analogous - Colors aside or astride each other on the wheel.
Analogous colors are often used to provide color interest in a seemingly monochromatic area. Compositions using analogous colors are often less intense than compositions using complementaries.
Triadic - Colors evenly spaced by thirds on the wheel.
The three primaries together have a triadic relationship. This often forms the basis for paint mixing. Compositions using triadics often seem balanced and subdued.
Tetradic - A pair of complementary color pairs, four in all.
Compositions using these relationships vary tremendously, often teetering on the edge of disjointedness.
Full color - Every color appears. Often the presense of so many colors leads to percieved dullness, lack of focus, etc, but it can be done well, too.
Warm colors - The half of the color wheel divided from the red side of violet to the golden side of yellow. These colors come forward in the piece regardless of supposed placement.
Warm Tones occur when a pigment reaches towards the warmer end of the spectrum. Blue-violet is a warm blue.
Cool colors - The other half, these colors recede in the piece.
Cool Tones occur when a pigment reaches towards the cooler end of the spectrum. Red-violet is a cool red.
Temperature at work :
If warm colors come forward and cool colors recede, then compositions with a warm foreground and cool background have more depth, which is often impressive or empty, while compositions with the opposite setup have less depth, and are often constricting or cozy.
Warm colors are of a higher intensity, and therefor can be used to attract attention to focal points.
Range and distance:
Range has to do with what parts of a value, hue, saturation, or temperature scales are being used primarily, and distance has to do with the space between the values used. Complementary colors are opposite on the color wheel, meaning that the distance is huge, but the range might be narrow, containing a minimum of only 2 percieved colors. Similarly, white and black are very far apart, but a composition using only them has little range. Often, distance lends "pop" to a piece, while range lends subtlety.
The most "pop" :
Typically, to have the most popping composition, splitting into simple distance dichotomies with little range is best. Take a pair of complementary colors, split them then into light and dark, saturated and not, warm and cool. Use onyl this palette and place colors in real quantities directly beside their counterparts (or close enough).
Natural Colors - Pigments taken directly from the natural world such as earth or plant dye
These were all that was avaiable for centuries and I consider them to yield far superior results. Such colors are true ultramarine (a process of grinding and firing lapis lazuli), cinnabrese, or sinoper, there terre's and the ochres among thousands of others.
Alchemic Colors- made on their own through chemistry
These colors are often used in modern painting but were seldom seen traditionally. Common colors include Chartruse, Phthalo, and other colors I find unattractive, but there are also very nice mimicks of traditional colors, such as synthetic ultramarine, that are often cheaper.
There's so much more just to get to a functioning vocabulary, it's like learning a new language. I'm tired though and this took me a while. While this is mostly about painting, all of the old rules apply to pixelling. Hope it helps.