The Martian 24 Hue Colour Wheel (click for full resolution)

Why do we need another colour wheel?

There have been numerous colour wheels over the ages, from Isaac Newton's in 1704 to Goethe's in 1810 to Wilhelm Betzold's in 1874 to modern "Traditional", Printers' CYMK and Physicists' RGB wheels. "Surely this ought to be enough!" you say. "It's all been done!" you say. "Colour has been well known for thousands of years!" you say... Well yes and no.

For a start: The "traditional" colour wheel is wrong. Just ask any physicist or qualified printer. Just because there are legions of oil painters and water-colourists the world over prepared to swear blue that the "traditional" wheel is the only true wheel, does NOT make them right!
Secondly: There are not enough hues in most wheels... either that or you are confronted with a continuum of hues. Neither is satisfactory.
Thirdly: Most wheels only give the primary shade of that hue, no darker shades and no lighter tints.
Fourthly: The names of most of the colours are either missing, incorrect or so clumsy as be useless.

The Martian Colour Wheel is based on the HSV cylinder but it uses 24 hues that have been corrected for brightness, hue distortion around the primaries and for the Abney Effect. It also keeps the full brightness of all the hue exemplars in order to match the richness of colour available on our RGB screens. There are also 2 dark shades for each hue and two light tints. (If the primary is over bright or over dark there may be 1 of one and 3 of the other but there are always 5 exemplars of each hue.)

The result is 120 colours that cover most the gamut available on a computer screen and most colours that you can see in the real world. Obviously, since there are an infinity of colours in any given gamut you can't cover ALL of them with 120, however, you can rest assured that there WILL be a colour on the Martian Wheel that is close to any colour you can find on a computer screen. There ARE a few exceptions, namely: very dark shades and mid to dark very unsaturated colours. I judge these to be less important than the brighter, more saturated colours and so, for the time being I have left them out.

The Martian Colour Wheel also NAMES every colour with a simple, recognisable, real world example! You may think that this is no big deal, but I assure you: IT IS!

With the Martian Colour Wheel you have a vocabulary of colour that will cover almost everything you can see. It will give you a way to talk accurately about colour that you have never had before. It will also give you a richness of understanding about colour that you never had as you learn to name colours accurately for the first time.

The Martian Colour Wheel is an essential part of the education of all people with colour vision. It should be on the walls of all primary schools the world over! Make it so!

What is colour?

Most painters think that they understand colour. They don't. They understand how to get the colour that they want on their canvas, or at least, something that will do. Most painters are labouring under the delusion that the 3 primary colours are Red, Yellow & Blue. This incorrect notion goes back hundreds of years and its basis is the fact that at the time, with the pigments available, those 3 colours could not be made by mixing other colours. They could not be mixed, therefore they had to be elemental. This is quite wrong as any modern printer knows. Modern printers using today's pigments, can mix up Red from Magenta and Yellow, and Blue from Magenta and Cyan. Yellow is the only one of the "traditional" primaries that cannot be mixed with pigments.

Printers may think that they understand colour and unlike most painters, they at least do have a real set of 3 primaries in Yellow, Cyan & Magenta that do more or less follow a sound theory. This is only because chemists have finally found some high intensity, transparent pigments that mix cleanly namely: Pthalo Cyan, Quinacridone Magenta and Arylide Yellow. These nice modern synthetic pigments make the subtractive theory of colour appear to work. However as any painter knows, as soon as you use normal opaque pigments it falls down.

Physicists think that they understand colour with their additive primaries of Red, Green, Blue and they have computer screens and cameras to prove it! Yes, it is they that understand best, with their additive system of colour that deals with pure light. However the system breaks down when used with paints, although it does work partially, thereby dispelling the idea that the subtractive theory has all the answers when it comes to paint.

The reality is that Colour is an extremely complex subject which cannot be explained by any simple theory. It is a tricky business because of the following:

It is a subjective experience that exists only in the mind. The human eye is stimulated by 3 colour sensors and the mind interprets that data. What you see is just an interpretation of the data, not the data itself.
Light in the real world is not composed of mixtures of three primaries but selections from an infinity of wavelengths through the visible spectrum and beyond. Such selections are never composed of a single spectral hue but 5, 10 or more precise spectral hues that are characteristic of the atomic and molecular structure of the material that is emitting the light. This is quantum mechanics that you can see! The colour of a nice pink rose that you see many be composed of 20 or more discrete hues, mixed together by your eyes and brain.
Real world hues are spectral hues, that is, they exist ONLY along the rainbow line from Red to Blue. None of the hues of purple and pink actually exist on the spectrum. Hues that are composed of a mix of Red and Blue exist only in the human mind, where the RGB colour wheel is part of the eye's interpretation algorithm. There is no "Pink" or "Purple" wavelength. The only reason you see Violet in the visible spectrum is due to a secondary peak in the red sensor sensitivity spectrum past blue. The brain interprets this second red peak the same as it would the primary red peak and assigns this weak blue along the purple line. In fact, it belongs in the blue. The term "Ultra Violet" is a misnomer as there is no "Violet" in the real world, only in the imagination. It should be termed: "Ultra Blue".
Surfaces in the real world do not behave purely as absorbers or transmitters but mixtures of the two so that in most cases neither the additive nor the subtractive theory of colour work properly. There are exceptions such as computer screens and transparent clean mixing dyes in colourless medium, but these are highly artificial, the real world is difficult.

What's so special about colour names?

"We've already got lots of colour names" I hear you cry. "We've got red, blue, yellow, green, violet, teal, pink, fuchsia etc". Well yes, that's true but when you look closely at them you find that they are not as helpful as you think.

Thanks to Physicists and Printers we have a good agreement on the precise meaning of Red, Blue, Green, Yellow, Cyan and Magenta, although even here there are problems: Is Green the full intensity of green pixel or somewhat less? Cyan and Magenta have predecessors from the art world of differing hues. Nevertheless, the precise definition of the 6 primaries is pretty well fixed.

The same, alas, cannot be said for the names of all the rest of the colours: Take "Pink" for example. It is used to describe anything from Purple to Red and in differing shades and tints. The same imprecision is also apparent for "Purple". We all agree on what "true" Blue is but there are a vast array of hues, tints and shades that are referred to as "Blue" yet are nothing of the sort including "Sky Blue", "Sea Blue", "Baby Blue" etc. The same kind of mess is also apparent with "Green" where there is a lack of distinction between "Green", "Emerald" and "Cyan".

It is not only a lack of precision that creates problems with colour names, there is also the horrendous matter of ascribing a real world exemplar to the WRONG colour! How this starts I don't know but before long you have the entire fashion industry and gullible folk the world over amplifying the error until the LIE becomes the standard and the truth is forgotten. Examples of this horrific practice are legion but include: Indigo, Teal, Fuchsia, Apricot and Lime.

"But there's already lists of colour names." I hear you say. "Just go down to you local paint shop and get their catalogue." Yes, you can pick up a catalogue of hundreds of names for any of the paint manufacturers, but there are problems with this naming approach that mean paint catalogues are NOT a solution:

Paint manufacturers do NOT cover the whole gamut of real world colours, partly because they don't have the pigments or the bases to cover everything and partly because they are only interested in making colours that are going to sell. People like pastel colours and high tints for their homes and so that is what is in the catalogues. Fully saturated colours are rare, as are clean secondaries.
Each manufacturer has its own name for each colour. There is no agreement.
The names that are chosen are either meaningless eg. "Serenity", "Enchantress" or "Porpoise Place" or inaccurate eg. "Salmon Pink", "Sage Green" or "Slippery Moss". Generally speaking they are simply meaningless.

There is however, the X11 colour names that no one even knows who compiled, yet became a sort of standard for web browsers. Like the ridiculous paint catalogues it contains numerous names that are inaccurate eg. "Olive Drab", "DarkSeaGreen", "Chocolate" or meaningless: "Peru", "Seashell", "Medium Orchid". Most of these names are simply inaccurate. So inaccurate in fact that they should never be used.

Then there is the list of colours on Wikipedia. It's anyone's guess who compiles these as most of them are simply WRONG! If you don't believe me go ahead and check them with real world examples, you will be as astonished as I was.

Colour professionals use the Pantone scheme where a very large number of colours are precisely specified with pigment recipes so that they may be accurately reproduced in the commercial painting world. This is all very well except that a) they are based around the painting gamut, not the computer screen and b) they use numbers not names, such as "17-1463" or "PMS 130". As a result they are useless for mainstream colour naming.

Finally there is the Munsell colour system. Munsell gave his hues names like "Blue-Green", "Purple-Blue", "Green-Yellow" etc. Colours were then further specified using numbers so the end result is too clumsy and academic to be of any use for our purposes.

It's hard to believe that authorities should be so utterly incompetent when it comes to naming colours but that is the sad reality. Be assured that the Martian Colour Wheel names its colours accurately using real world examples. You can read up on each colour here and see a photograph next to it of the real thing so that you KNOW you're using the right word!

Dive Into The Wheel

We are all fascinated by colours. We have been immersed in them since we first opened our eyes and they are as much a part of our lives as food or movement. The colours of the natural world are truly amazing and deserve to be accurately named. I have provided a vocabulary of 120 accurate names for the most useful 120 colours that can be seen on a computer screen. It is up to each of us to learn these names and to use them when referring to a given colour. Instead of saying "pinky-blue" you could say "spectral violet". Instead of saying "pale-green" you could say "chrysolite". Instead of saying "dirty-yellow" you could say "wasabi".

The story of each of these 120 colours is fascinating in itself. I invite you to dive in and check out a given hue for yourself. I have created a separate page for each hue and you can investigate them all here.

Warren Mars - 2014

Excelsior!

Epilogue

Since I uploaded my colour wheel section 8 years ago it has become the most viewed thing on my very extensive and varied website. I have received numerous emails from people telling me how interesting and useful it has been and in some cases they have given me details of how they have used it in the work. Naturally I am glad that my work has been of use and I hope it will continue to be! Thank you to all that have taken the time to look at my colours in depth!

When I first put up the wheel it was not finished and I only put it up because I thought it was far enough advanced to be of interest and use. I knew that there was more work to be done and probably changes to be made but I was busy with other projects that I could see would take years so I uploaded what I had and put the wheel on hold.

Not only were there second colour exemplars and text missing but most importantly I hadn't corrected the wheel for the Abney effect so some of the tints needed to be moved. You can read all about why these changes were required here. I felt that some of the hue angles also needed to be moved to give a better sense of equal chromatic spacing. I made these changes to the wheel some years ago on my computer but didn't adjust the pages detailing the colours in depth, waiting for the free time to do a proper job. So long as I didn't upload the changes there would be no problem and I could make the adjustments in my own time.

That was fine but then in 2020? Google decided to force everyone to use HTTPS and I had to change the HTML on all my 400+ pages... This meant I had to upload my colour wheel changes even though they were not ready. There were a few things that didn't match, which some of you noticed and I apologise for any inconvenience or frustration.

I have now fixed the main problem of realigning the adjusted wheel with the colours in depth pages. This meant moving some exemplars: celadon was moved into the emeralds, Chayote was moved to the greens, variscite was removed altogether, blue agave was renamed aquamarine, horned spurge and iceberg lettuce were introduced as the tints of clover. There were also a number of new exemplars added, primarily around emerald.

I apologise for any inconvenience in changing the wheel. If you have printed it out you will need to print out the new one and relearn the area around emerald. It is better to have errors corrected though, albeit at some inconvenience, than to labour under them for eternity.

The colours are now, hopefully, fixed in place and I don't plan on changing them in any serious way. I will however be adding missing exemplars when I find them and I may make a few tweaks as errors or improvements occur to me or if lots of you demand them.

Consider the wheel now "mostly finished" and continue to use it. I will at some point attempt to find a way of printing it out accurately although be warned that that may not be possible as the printer's gamut is not the same as the screen gamut.

Happy colourising!

Warren Mars - 2023