Last year a student, Kaori, from Japan spent some time with me at Leeds and we spoke a lot about how to use colour effectively in maps and in urban design generally. One of the issues we were looking at was whether the maps’ features would be discriminable to colour-blind observers (of which, of course, there are many). So I was interested to come across an interesting article today relating to this very issue.

Apparently the following image appeared in the Guardian newspaper:

It’s a colour-coded map of London. It shows areas of deprivation with red being the most deprived. It met with much criticism, however, and many people said they had difficulty in discriminating between the colours. Of course, colour-blind observers most commonly have difficulty discriminating in the red-green region of colour space. The company who made the map engaged in a debate with users on twitter and created variously different coloured versions of the map, subjecting each to the public vote via twitter. The map below is one of the later versions.

For further details please refer to the story at The Guardian here.