Colour

For this challenge, I thought initially of putting up a white, three by two picture; it contains all of the colours! However, since I had already explained the nature of colour in the first one of these challenge blips, I thought this would be a little excessive.

I decided that I would try and take a picture with all or most of the spectral colours displayed in it and found this particularly difficult to achieve. Glancing at one of our many bookcases I saw that there, all together on one half of a shelf were most of the colours I was looking for; this is one of my reference shelves in our bookcases. It contains red, orange, a type of yellow, green and blue, although to say it contained indigo and violet would be stretching it a bit. (The book to the left of the green Biology book is a very faded yellow.)

As a matter of interest, Newton, when he first described his experiments with the spectrum identified seven colours, red, orange, yellow, green, blue, indigo and violet. The majority of people do not have the same spectral response for the blue cones of their eyes as Newton did and can only resolve red, orange, yellow, green, blue and violet, not having sufficient sensitivity in the indigo part of the spectrum to differentiate it from blue or violet. So most people can only see six colours!