Cotton Reels Help

General
This is something to help in choosing colours for a Web page. Only by actually viewing colours against one another is it possible to decide if they are effective. The Colour Sampler is intended to let the Web page author play with colour.

How should it be used?
Two palettes are available. The first is the standard colour cube, it can be viewed in 3 different ways but each displays exactly the same range of colours. The second is the standard set of Netscape named colours, these will work on both Internet Explorer and Netscape Navigator. The named palette can be seen in two ways, either ordered by colour value, or by name.

All the palette displays are selected using the radio buttons on the top right.

What next? When a palette has been chosen simply pass the mouse over to see the colour displayed below. If you like the colour then click! The selected colour will then be displayed in one of eight selected areas. Alongside each of these areas is a radio button, the colours will drop alongside whichever button is selected. Alternatively, at the bottom of the screen is a radio button that if selected will cause the colours to drop in rotation.

The clicked colour value will also be displayed in a text box, this will either be the colur name or the RGB hex triplet colour value depending on the mode in use. These values may be used directly in HTML, the best method is to copy and paste these values.

Why is the palette so restricted?
At this point in time, to find colours that can be seen across the vast range of browsers then the range of colours used must be restricted to somewhat less than 256 colours. This is only because very many computers that are used to browse pages are only capable of displaying colours from an available palette of 256. Further, the Windows operating system reserves 40 colours for system use so that Windows display objects can be displayed properly. This leaves only 216 free colours to fill the palette with. The Colour Cube, see below, displays 216 colours. Using these colours will help ensure your page displays the way you want on systems with 256 colour displays. However, in reality you may still get unexpected results. The best advice is to switch your display to 256 colours and take a look!

What is a Colour Cube?
No more than an even range of colours. The colour is determined using an RGB hex triplet (e.g. #FF9933). The colour cube is made of all RGB combinations using #00, #33, #66, #99, #CC and #FF. To see this, simply move the mouse over the selector palette and notice the RGB values change in the display hint as you move from one colour to another. These values were originally chosen because early Netscape browsers were engineered to give best results with these values.

Additive primary colours
Colours that can be added to black to mix a new colour. The additive primary colours are red, green, and blue.

Subtractive primary colours
Colours that can be subtracted from white to mix a new colour. The subtractive primary colours are cyan, yellow, and magenta.

Describing colours
Colour can be described in terms of components. The components most often used by imaging professionals are hue, saturation, and brightness. A hue is what we normally think of as a colour. A colour's hue fixes its place in the visible spectrum of light. The saturation of a colour is how "pure" or "strong" a colour is. Neutral grey is said to have zero saturation. The brightness of a colour refers to the intensity of light that is reflected or transmitted by an image.

The terms tint, tone, and shade are also well-used in colour imaging literature. A tint of a colour is obtained by mixing its hue with white. A tone of a colour is created by mixing a hue with grey. A shade of a colour is made by adding black to its hue.