Misconception: The rainbow (or spectrum) contains all the colours we can see.
Concept Corrected: We perceive many more colours than we see in the rainbow (or spectrum)
Close up of the range of hues seen in a rainbow.
When we look at a rainbow, or send a beam of white light through a prism, we see a very particular set of colours (called a spectrum).
Sometimes you may hear that the rainbow contains all the colours you can see - but this is not true! Look closely at the rainbow or spectum. What colours are missing? Where is brown or pink or grey or magenta or purple …
Sending white light through a prism creates a spectrum.
In a spectrum, we see a range of the most vivid hues ranging from violet to red. Pale, dark and muted colours are not part of the visible spectrum, nor are the achromatic colours. Recognizing all the ways to describe colour helps us see that the spectrum shows us a limited view of all the colours we can see.
Range of non-spectral hues: purples, magentas, red-purples (image courtesy David Briggs.)
There are additional hues which are not part of the spectrum: magentas, purples, red-purples, etc. These are called the non-spectral hues.
Note that most colours we see in our everyday lives are not the vivid colours seen in the spectrum.
