Additive vs. Subtractive Colour

The additive colour model (RGB) is used for digital displays and works by combining red, green, and blue light to create a wide range of colours. As you increase the intensity of these three colours, you move towards white. The subpixels in the display you're reading this on can independently increase or decrease brightness of red, green, and blue to create 16,777,216 colours (each subpixel can have a brightness setting anywhere from 0 to 255)

On the other hand, the subtractive colour model (CMYK) is used in printing. It involves mixing cyan, magenta, yellow, and black inks. As you add more colours in this model, you move towards black. This is because printed materials start with a white background, and the inks subtract or absorb light to create colours.

When designing on a computer, you'll be working with RGB colour values which are often expressed HEX notation, which is six alphanumeric values following a # sign. When looking for colours to use in your designs, you'll want to copy these HEX values across programs to ensure you're getting the exact colour. The simulation next to this text shows how HEX values change, and how CYMK values can also be approximated using this system.

Understanding the difference between RGB and CMYK is crucial when designing for digital platforms versus print materials. RGB colors often appear brighter and more vibrant on screens, while CMYK colors are better suited for achieving accurate printed results. When designing for digital platforms, you can take advantage of the full RGB color spectrum. In print design, however, you need to be mindful of how colors will convert from RGB to CMYK during the printing process

Colour Harmonies

In colour theory, we start with three primary colors: red, blue, and yellow. By combining these primary colors, we create secondary colors: orange, green, and purple. This color wheel forms the basis of color mixing. 

Complementary colours are pairs of colors that are opposite each other on the color wheel. When placed together, complementary colors create visual contrast and enhance each other's vibrancy. Analogous colours are hues that occupy similar spaces on the colour wheel and can elevate a particular mood or style associated with that colour. Monochromatic colours belong to the same hue, but have different saturation and brightness values. It creates a simple and elegant look with a unified feel. Split complementary schemes combines a base color with two colors adjacent to its complementary color, providing contrast while maintaining harmony. Lastly, a triadic or tetradic colour scheme consists of three or four colors equidistant from each other on the color wheel. They offer a vibrant look but can be quite visually busy if overused.