Colour spaces are ways to organize colours into specific categories. A colour space can be arbitrary, where colours recognizable in the physical world are assigned swatches and names, or have a mathematical organization plan. Colour spaces are conceptual, and they help you understand the types of colours a device can produce.
What Are the Types of Colour Spaces?
Think of a colour space as encompassing any shade you can imagine based on the three primary colours — red, blue and green. Every colour arising from any combination of these three falls within the colour space. Typically, colour spaces are developed on a diagram, which can be RGB or CMYK. How do you choose a colour space? Dive into the definitions below to learn the basics.
Lab Colour Space
One of the choices for measuring colour is using lab colour space. This space has the same components as others, though it is divided into lightness (L*) and two colour components (a* stands for red and green value and b* stands for blue and yellow). The “lightness” is kept separate from the other parts because when you adjust it, the change more closely resembles human vision. In other words, if you use a lab colour space and adjust the lightness, the outcome will look more “correct” to the human eye.
RGB Colour Space
Red, blue and green are the primary colours, each of which is visible to the human eye. Visible colours are considered to be combinations of these three. To measure the possibilities of every colour you can mix with red, blue and green, you can model an RGB colour space, which is a three-dimensional plane in the shape of a cube with each colour on an axis — a point’s position within the cube indicates its colour makeup and saturation. The majority of digital images use an RGB colour space.
There is some debate over RGB versus Lab colour for reproducing images. In many cases, sticking with RGB will suffice, though projects requiring careful colour correction and toning can benefit from the adjustment capabilities of Lab.
CMYK Colour Space
The cyan, magenta, yellow and key (black) colour space is another option, which is typically used in printed materials. When working with CMYK, you start with a white base and add the ink. The ink absorbs and reflects different light levels, giving you the desired colours.
