The Qualities of Colour
On reading about the qualities of colour in the introduction section of Part Three, I found certain aspects confusing. Confused as to what was the difference between saturation and brilliance and also when trying to comprehend that when mixed digitally, the primary colours did not produce the results that I would have expected.
Further reading has helped me gain a bit more insight into the qualities of colour and I thought it would be useful to summarise my this as follows.
Freeman (2005, p10) notes that, when used well, colour can be the most powerful element in a photograph. It differs from the other graphic elements as it can invoke physical, physiological and psychological responses. These subjective responses are sparked as the eye and brain react to a colour’s individual wavelength.
The idea of primary colours, red, yellow and blue (RYB), being mixed to create green, violet and orange is something that I learned many years ago as a child. Freeman (2005, p17) refers to these colours as ‘painters’ primaries’, and this system of mixing colours as ‘colour by reflection’.
However, in digital photography, processing and printing the three primary colours used for display are red, green and blue (RGB). I have found it both interesting and slightly confusing to learn that, digital colour, RGB, is coloured light and this behaves differently when mixed than the painters’ primaries do. For example, combining red and green digitally produces yellow, green and blue creates cyan and a mix of blue and red results in magenta. A combination of all three, RGB, creates white. Combining RGB is known as light transmission. The illustration in Freeman (2007, p114), similar to the one below, shows this using torches to illustrate the ‘light’ factor.
There are three qualities that define a colour; hue, saturation and brightness.
When most people refer to ‘colour’ they usually have in mind the hue. It is the fundamental quality of colour. The quality that differentiates blue from green or orange from yellow for example.
I initially found it difficult to understand the difference between saturation and brightness although I recognised that both are modulations of hue. Freeman (2005, p20) describes saturation as a variation in the purity, or intensity of a colour. As colours become less saturated they become more grey and appear ‘muddier’ and ‘dirtier’. Maximum saturation would contain no grey while minimum saturation would contain mostly grey.
In the real world, colours become unsaturated when they are mixed with white, black, grey or complementary colours. The majority of colours found in nature are adulterated, a mixture of hues, resulting in a palette of greys, browns and dull greens.
Brightness, also known as brilliance, is the lightness or darkness of a colour with white and black at the extremes of the scale. It differs from saturation in that when the brightness is varied the colour remains pure and unadulterated.
The effect of brightness varies according to the hue. For example yellow is the brightest and lightest of all colours. It can only vary between a medium tone and a very light. Dark yellow does not exist unless it is degraded, becoming ochre.
Brightness also differs with varying light levels and sources, a topic I will look at in more detail in the next exercise, What makes a colour?
Freeman, M. (2007) The Photographer’s Eye. Lewes: ILEX
Freeman, M. (2005) Digital Photography Expert: Colour. Lewes: ILEX
Open College of the Arts. Basic Colour Theory. Barnsley: Open College of the Arts