March 22, 2019
For choosing the colours when designing a painting, experts recommend to always use red. Statistics show that paintings with the colour red sell better. Is there such as the “right” colour or the “wrong” colour when it comes to art? Or the idea about red is just a misconception.
Perhaps it is not red, but the colour: yellow.
To fully grasp what makes yellow so unique, we need to understand how the human eye is structured but mostly how our eyes react to light.
You may already know that the back of the retina is covered in light-sensitive neurons known as cone cells and rod cells. Each of the three types of cone cells is sensitive to different ranges of light. Although these ranges overlap, blue represents short-wavelength, green stands for medium-wavelength, and red means long-wavelength. The rod cells are primarily used in low-light situations, so we don’t have to be worried about them for now.
When light enters our eye and hits these cone cells, the cones get excited and send signals to our brain through the visual cortex. Naturally different wavelengths of light excite different combinations of cones to varying levels. This is what generates our perception of colour. The red cones are the most sensitive and the blue cones are the least sensitive to light. Our brain takes the signals of light intensity from the cones and turns it into colour information.
To see red or green, our brain finds the difference between the levels of excitement in the red and green cones. This is the red-green channel.
To get “brightness,” our brain combines the excitement of the red and green cones. This creates the luminance, or black-white, channel.
To see yellow or blue, our brain then finds the difference between this luminance signal and the excitement of the blue cones. This is the yellow-blue channel.
We see blue when low-wavelength light excites the blue cones more than the green and red. We see green when light excites the green cones more than the red cones. We see red when only the red cones are excited by high-wavelength light.
Here’s where it gets very interesting.
We see yellow when both the green and red cones at their peak sensitivity. This is the highest level of excitement that our cones are capable of generating, aside from seeing pure white. Yellow occurs at peak intensity when the lens and cornea of the eye block shorter wavelengths, reducing our sensitivity to blue and violet lights. This, combined with the neuronal nirvana resulting from the overlapping sensitivity of the red and green cones, is the reason why yellow seems to be the brightest colour in the colour spectrum, making it the most unique and ‘useful’ colour for creating art. It certainly gets everybody’s attention.
If you study Van Gogh’s paintings from 1886-1890, you will clearly recognize the repeated presence of yellows. Overtime, Van Gogh’s color palette changed from more earthy tones to brighter colours. As with many things surrounding Van Gogh, there isn’t a clear reason for his use of yellow. Was it due to a vision problem, or his drinking Absinthe, or was it simply a personal preference?
I let you decide and draw your own conclusion.