The colour circle is the first colour system offered to you by Calamus. You will see above all the colour circle itself, in which the fundamental colour areas of the RGB-CMY colour system of the 32-bit colours are displayed. Thus you can quickly get a feeling for the mixing of colours by clicking on a colour shade that is closest to the desired colour.
A colour square now appears within the colour circle, in which the colour clicked on appears at top right, and is mixed with various amounts of white towards top left and black at bottom left. If you click anywhere within the colour square (and only then!), the colour that you have clicked on will be adopted as the colour value, and shown in the adjacent colour preview field immediately so that you can check your selected colour. You will also see the colour value reflected in the respective colour sliders, with numerical readouts to their right.
At the right of the colour circle you are offered various colour systems for this 32-bit colour system. Please note that apart from CMYK all other colour systems are currently handled internally by Calamus with 24-bit colour depth. Therefore the following applies: RGB is internally the same as CMY or as K or as IHS. Only CMYK is really a 32-bit colour, which is already pre-separated for the colour separations into the four process colours of the Euroscale. If you are not familiar with colour separation processes, please choose for your own document colours directly the pre-separated CMYK colours if possible. In this way you can read off directly from the four colour sliders of a CMYK colour how large a portion of this colour will wind up in each of the four films when you imageset a document with this colour.
Colour fill-patterns
The colour that you define need not be just a plain colour, but
may also be modulated by one of 24 different fill-patterns. To do
this, please click on the Pattern
button, which opens the
following dialog box:
If you click on one of these fill-pattern fields, then the previously plain colour field will display the dark parts of the chosen pattern in that colour, normally contrasted by a black background.
When you close the dialog afterwards, you will see a new
Background
button. This button is only visible if you have
assigned a fill-pattern to a colour. If you click on this button, you
can use the colour sliders to define a colour other than the preset
black as a background of the coloured fill-pattern. You can even
choose the colour system for this colour freely.