The rainbow only lists seven colours but as my ongoing colour tests show, there are a lot of different options out there for each of them.
This week its blue, then next week will focus on both indigo and violet. When I've finished all the tests, I will use the colour swatches to decide which of the many tubes of colour can be used up and not replaced, and the ones for which I need to find an alternative. There has been much information about potential health risks from cadmium, so I am especially keen to find some other yellows and orange to use. Some of the other colours are very similar and I need to decide which to rule out and which to keep.
From an artist's perspective, colour is often analysed using a colour wheel. This has twelve sections, and is built around the three primary colours - red, yellow and blue.
In my Instagram and Facebook posts, I have often referred to a colour that is warmer or cooler, and that describes the influence of the colours either side. So, for example there are yellow-orange colours which sit between yellow and orange on the wheel.
Sometimes I think back to when I first started to paint regularly. We were in Spain and I went to a studio run by a lovely Spanish teacher Estefania. Tuition and conversation was in Spanish so as well as learning a lot there about working in acrylics, I was able to practice and improve my language skills. There was a big focus on colour mixing. Students were only supposed to use magenta, cyan, process yellow and white; everything else was mixed from them. We started by painting a colour wheel; mixing red and yellow to make orange, the adjusting the amount of each colour to make red-orange or yellow-orange was relatively easy. The most difficult to mix was black; not usually depicted on a colour wheel but in our case we were told to paint it in the centre.
When I wanted to switch to working in oils, there was strong resistance because the mediums are smelly and upset some people, Instead I was told to try water soluble oils. To test out this new medium, I went back to basics again buying just three colours and white. Having subsequently worked in traditional oils, there is no comparison, but I was able to create a painting from just those four tubes of paint. The result is 'Frangipani 2' in the Reflections of the Nature gallery..