Monthly Archives: March 2011

white taxis

In 2009 I blogged about a row in Derby about the yellow colour of taxis. But times change. Things move on, Today I am reading about a problem in Durham – for those who don’t know, Durham is in the north-east of England – about white taxis!! Apparently, this week ten drivers stormed out of a meeting with councillors over a proposal to adopt a policy for all-white colour taxis in the county of Durham. The argument for white taxis is that it would make them stand out and ensure that customers knew which taxis were legitimate. Sounds pretty sensible to me. It would work because white is a very unpopular colour for cars in the UK. I have heard that second-hand car salesmen refer to white as six-week white because it takes 6 weeks longer to sell a white car than other coloured cars. Whereas in other parts of the world, I have noticed in my travels that white cars are quite popular. Perhaps there is a business opportunity here – to export the unpopular white cars to places where they may sell for a premium.

RYB primaries

There are two phrases I keep seeing written down all over the internet that cause my blood pressure to increase.

The first is that the colour primaries are red, yellow and blue (RYB). And the second is that the primaries are colours that cannot be made by mixing other colours. Neither of these statements are true, of course.

The first statement makes no distinction between additive colour mixing (of lights) and subtractive colour mixing (of paints and inks) but subtractive colour mixing is normally implied. However, RYB is a relatively poor choice for three colour primaries. The range of colours that can be produced is actually quite small. For most painters and artists it doesn’t matter because very few work in just three primaries – if they did so they would probably be frustrated by the small gamut of colours achievable. Many artists (painters) will use 10 or more basic colours to mix their palette. However, there is a group of people who care passionately about the gamut of colours that can be obtained by mixing three colour primaries – that is the people who work for companies such as HP and Canon. These companies make CMYK printers for the consumer market and their jobs depend upon consumers liking their printers. They understand that the largest gamut (in subtractive mixing) can be obtained if the primaries are cyan, magenta and yellow (CMY). The teaching of RYB as the (subtractive) primaries should be stopped. It’s already gone on for far too long.

One reason I don’t like the teaching of RYB as being the subtractive primaries, in addition to the fact that it is wrong, is that it confuses people who are trying to learn colour theory. This is because red, yellow and blue seem to be quite pure colours and this encourages people to hold the second belief I don’t like which is that the primaries are pure colours that cannot be mixed from other colours. If people understood that the primaries were CMY it would be less tempting to hold this belief about the purity of the primaries. Of course, if you make a palette of colours of three primaries then it is true that no mixture of two or more colours from that palette can match any of the primaries. However, there are other colours (that are outside the gamut of the primary system) that could be mixed together to match the primaries. This false notion of purity confuses the real issue – that is, that the subtractive primaries are cyan, magenta and yellow because the additive primaries are red, green and blue. Look at this picture below:

The additive primaries are red, green and blue and the secondaries are cyan, magenta and yellow. Correspondingly, the subtractive primaries are cyan, magenta and yellow and the subtractive secondaries are red, green and blue. Simple.

I wrote about this before so for a slightly different perspective see my earlier post.

Perhaps I am so agitated about it today because I am just watching England getting trounced by Ireland at rugby when the Grand Slam was so tantalisingly close. Or maybe I will feel just the same tomorrow.

Design is everything and nothing

It’s possible to say that everything is designed. When we think of design we often think of fashion design or graphic design, or perhaps automtotive design or software design. But everything is designed. When we put a meal together, couldn’t you say we are designing? A chef is a food-designer!! When we are arrange our furniture, aren’t we engaging in interior design? Isn’t a chemist engaging in design at the moulecular level? Thinking like this leads to the idea that design is everything. However, if design is everything and everywhere then it is no thing and nowhere in particular. So if design is everything then it is also nothing. Discuss.

colour choice

I met a chap from an Advertising Agency today and was surprised when he offered me his business card. He didn’t offer me a single card; he offered me a selection from a fan of cards of different colour.

I chose the purple one and was then surprised when my PhD student told me she has chosen the same colour. A clever experiment in colour preference perhaps? Next time we meet I’ll have to ask him for the data. I hope he is keeping a record of which colour cards are proving most popular.

If you are interested in this you may like to have a look at my colour preference poll. After you take part in the poll (takes only a few seconds) you can see the results of the study so far.

totally colour blind

I was recently writing about colour blindness in the context of design and noted that most colour blind people see colour – it’s just they have poor discrimination and some colours look the same to them whereas to a so-called normal observers they would look different.

People who don’t see colour at all are rare. But I was just reading about one, Neil Harbisson, a classically trained pianist who has been colour blind since birth. He suffers from a condition called Achromatopsia which means he can only see the world in grey. However, he has recently being used a piece of technology that allows him to hear variations in colours. The eyeborg helps translate colours into sound and transforms the colour information picked up by the built-in camera into sound frequencies. For example, when he looks at a red, for example, he hears an F (= 349.23Hz); if he sees a yellow he hears a G. For more information see

I wonder what this would feel like. Of course, synesthesia sometimes occurs naturally. That is, some people can hear colours, see sounds, taste numbers etc. I sometimes think that Kandinsky (the artist who worked at the Bauhaus) may have been synesthesic because of his interest in the relationship between colour and shape. Quite possibly, sensing the world in a way that is different to how most people perceive it may me an advantage to an artist.

colour blind designers?

Is colour blindness a problem in design? Colour blind is rare amongst females but is very common amongst males. Approximately 8% of all the men in the world have some form of colour blindness. Colour blindness is a bit of a misnomer of colour; most colour-blind people can see colour but confuse colours that so-called normal observers can easily distinguish between. The most common case is red-green colour blindness and such sufferers find it hard to tell reds and greens apart.


But does design take this into account sufficiently? One area where there may be a problem is in the gaming industry. I came across the following comment today where someone is reporting a problem using Call of Duty (a game I don;t play but which I understand is quite popular) on the Xbox. Apparently, the Gamertags of all the players are either green if they are on your team, or red if they are an enemy. Oops!! I wonder how much of a problem this is. The problem is probably greatest when colour is used to convey information (as in this case, friend or enemy) rather just for aesthetics (where the information may be conveyed by contrast alone).