creating a good color scheme

A color scheme is a number of colors which are expected to work together as a unit. A scheme can be pure black and white, can be made up of gray tones, of different values of one hue, or it could be made up of many different hues.

A widely held (and hugely mistaken) assumption is that this is a random thing, based upon personal preferences. In truth there are physical laws which determine the harmonic relationships between hues and these involve the color wheel:

The above screenshots come from one of the greatest online applications around, the Color Scheme Designer, which lets you work with the color wheel - for free!

There are three tabs on this: The first one shows you the full spectrum of hues and lets you make your initial choice, based upon the relationships between the hues. These are monochromatic, complimentary, triadic, tetradic, analogic and accented analogic (which is actually just a variant of complimentary). Of these, my advise to all beginners is to use pure analogic relationships. This works with hues which are closely grouped upon the wheel and this set up will usually give you the easiest results to work with. 

The second tab lets you adjust the contrast and the saturation and brightness values of your scheme. Again, if you are a novice stay away from high contrasts for now and go with saturation and lightness values only - trust me, much much easier...

The third tab will then let you copy paste all of the hex codes of your colors into an image editor or into a CSS/HTML code. And if you look on the top menu there is even an export option which will create different things like a photoshop palette or a CSS list.

 (Suggestion:  Color wheel apps for designers (which, in the end, do the exact same job) usually cost a fortune whereas this hugely useful service is provided for free. So, why not make a donation also?   ;-) 
http://colorschemedesigner.com/

And then, another cool place for color is colorlovers, a social networking community revolving around color and patterns. Here you can download/upload color schemes and patterns to share with others. Very nice too! 

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