Do you see what I see?

Hello, hello. Welcome back to my wonderful world of colour.

Or in this case, perhaps not?

I just took this test here.

Luckily for me, I am part of the 94.5% of New Zealand‘s population that doesn’t exhibit signs of colour blindness.
I am one of the lucky 259 women who can identify a blue hue from a purple one, the 260th woman might see them both as blue. For men, colour blindness is much more common with 1 in 12. 

And when I say luck, for the majority of cases, being colour blind is almost a luck of the draw.

You see, colour blindness is a genetic mutation passed down from your parents.
The affected gene is carried on the X chromosome.
Women carry two X chromosomes (XX).
Men carry one X and one Y chromosome (XY).

You get one sex chromosome from your mum (it’s going to be an X, that’s all she has).
You get your second sex chromosome from your dad (it could be X, making you a girl orrrr it could be Y, making you a boy). 

The genetic family tree below shows the potential offspring of a non colour blind female who carries the mutated gene on one of her X chromosomes AND a non colour blind male.

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Both X chromosomes must carry the affected gene for a girl to be colour blind meaning her father MUST be colour blind.  Only having one affected X chromosome will result in that girl being a carrier and she may or may not pass on that X affected X chromosome to her own children. 

Colour blind men can only pass on affected X chromosomes to their daughters, as boys get their Y chromosome from their father. 

Naturally speaking, nobody can determine whether you will be a boy or a girl.
Nobody can determine whether you get your mum’s dud X gene carrying the colour-blindness genetic mutation or you get her other one.
So the way I see it, it all comes down to luck.

As I mentioned in my last blog, two clever guys by the names of Thomas Young and Hermann von Helmholtz came up with the trichromatic theory of vision involving colour receptors. You can read all about it here. 

cones

Our red, green & blue cone photoreceptors! 

At the back of the human eye, there are cone photoreceptors and rod photoreceptors. For the majority of cases, it is faults within the cone photoreceptor cells which lead to differences in the way a person might see colours.

Colours through normal vision (when all three cones are in good working order) generally look a little something like this….

colourblindew
However, have a browse through my table and have a look at how the different kinds of colour blindness affect the way in which these colours are seen. 

table

For people who are colour blind, some tasks in life can be made pretty tricky. This includes, but is not limited to, interpreting traffic light signals or coloured charts, or as simple a task as picking ripe fruit and veges at the supermarket. 

Unfortunately, there is no cure. However, it’s not all bad news. Modern technology advancements have contributed to helping out our colour blind pals. Apps have been created to help coordinate colours specifically for those trying to find an outfit that doesn’t clash. Some apps allow for a photo to be taken and all of the colours within that photo are then able to be identified with a simple tap of the finger. 

Also, technology in the optical world has now made colour-correcting glasses for people with red-green colour blindness that look exactly like any other pair of glasses. Which is pretty damn cool.

So next time you’re picking out those bananas at the supermarket and you can easily tell which ones are ripe and which are not, be grateful that you aren’t in that small, unlucky 5.5% of New Zealand’s population. 

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Do you paint, print or photograph? Here are your primaries.

Hello again!

In my first post (which you can find here) we left off with genius man Sir Isaac Newton conducting a great experiment which made rainbows appear on his walls. colourwheel3-100

By doing this, he proved many great things! However, this experiment also led him to creating a colour wheel or a circular diagram showing how colours relate to one another – kind of like this one over here to the right. 

If we start at red on the left, we see the colour progresses to dark orange, light orange, yellow orange, yellow and so on from colour to colour – pretty self-explanatory right?

Well this is where we get to today’s topic – primary colours + their accompanying colour models. And we’re going to get started with some basics. 

Primary colours are most simply described as colours that need not be mixed with any other colour to be created. They are the purest forms of that hue. 
However (generally-speaking) you can mix primary colours to create any other colour you can dream of, which is a pretty great thing. 

In Newton’s prism experiment, he decided that the three primary colours were:
color wheel-100

  • Red
  • Yellow 
  • Blue 

This traditional trio of primary colours makes up the RYB colour model also known as the colour wheel model.

 

In between these primary colours on the wheel you’ll also find secondary colours. colourwheel4a-100These are hues which are made from the two closest primary colours to them in the wheel. 

For example:

  • Red + Yellow = Orange
  • Yellow + Blue = Green
  • Blue + Red = Purple (violet) 

The remaining 6 colours left on the wheel are tertiary colours and are made by mixing primary and secondary colours together, it’s as simple as that! 

colourwheeltert-100Since Newton’s discoveries, science has progressed in leaps and bounds, and as we learn more about light, it’s motion and how it interacts with surfaces like the human eye, the RYB model has become almost redundant. It is now really only used in the fine art world when mixing tangible pigmented paints. 

During these aforementioned leaps and bounds made by science, it was found that red, yellow and blue were not in fact the best colours to combine when it came to presenting media through electronic systems using light e.g. TV, computer screens or photography.

In fact, red, blue and green are known as light primaries and combine in different intensities to around 216 different colours suitable for use through electronic screens. This combination creates the RGB colour model.

The RGB model is also known as the additive model. This name refers to the addition of different intensities of red, green and blue superimposed (overlaid on each other). The colour seen is dependant on the intensity of each colour. Complete intensity will result in white (as seen in the middle of the diagram) whereas no intensity will result in black.

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This colour model has been important since long before the explosion of technology. In the 1800’s, two scientists Thomas Young and Hermann von Helmholtz came up with the Trichromatic theory – that the way in which humans see colours is based on ‘colour receptors’ in our eyes – more specifically red, blue and green receptors. 

It was only these three receptors that were needed to see any and all colours on the spectrum. They thought that when each receptor was active, you would see the respective colour. If two were active at the same time – say your green and red receptors were active, you would be seeing a yellow hue. To see white, all three receptors would be stimulated equally. 

The Young – Helmholtz theory is still valid today explaining the aspect of colour vision associated with receptors.  

Quite literally the opposite, the subtractive model is also known as the CMYK model – the third and final colour model we’ll be looking at today. It involves cyan (a funny word for bright, light blue), magenta (a funny word for bright pink), yellow and black, called pigment primaries and it is mostly used in the printing world with inks and dyes. cmykmodel

As we saw at the end of my first blog, white light is made up of all the colours in the spectrum. In the CMYK model, white light is reflected off of a surface that has varying amounts of cyan, magenta and yellow inks upon it (the amounts are dependant on the colour aiming to be produced). The inks interfere with the white light, more or less ‘break it up’ and therefore the light that gets reflected back, is seen as a colour. 

On a piece of paper fresh out of the printer, the three colours are arranged in little dot patterns called rosettes that the human eye can’t make out unless looked at extremely closely. The CMYK colour model can actually produce many, many more colours than the RBG model because of this patterning.

rosette

INK PRINTED ROSETTES

So next time you go to fill up those (ridiculously expensive) printer inks yet again, or are about to paint the next Mona Lisa, or maybe just as you’re reading this blog and looking at all the pretty colours, think about these models, the clever people that created them, and how cool the world really is in colour.

 

The Beginning of Colour.

Does anyone else ever find themselves looking at black and white photos or watching a black and white movie and end up imagining an entire black and white world?
As though colours just… didn’t exist yet?
As though colours were a thing of the future“?

I’ve found myself intrigued with that thought before… But I can confirm that the world has always been full of colour. Now I want to explore the “beginnings” of colour and some of the theories surrounding it. 

Our First Colours (according to the Greeks).

Coloured pigments like red ochre have been used since prehistoric times, evident from the cave paintings found all across the world, some older than 40,000 years. 

However, some of the very first documented ideas us humans had about colour itself were back in the BC days beginning with Greek philosopher Empedocles of Akragas.

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EMPEDOCLES

Empedocles, and many Greeks for that matter, believed in 4 elements which make up everything that you see, each with their respective colour. 

These being:

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Alchemy symbols for air, water, fire, earth.

  • air = white
  • water = black
  • fire = red
  • earth = yellowish green

This confused people of the future. Could the Greeks only see 4 colours? Was something wrong with their eyesight? Were they colourblind?

No. They were not colourblind (at least not every single one of them).
They quite simply, only had words in their language for those 4 colours alone.

After a few other guys tried their hand at figuring out colours and applying an array of scientific, religious and artistic methodologies to them, it was Aristotle who really started the party when it came to colour theory.

Aristotle-100

ARISTOTLE

To the Greeks, black (darkness) and white (lightness) were primal colours.  All other colours were different mixtures of black and white. 

Aristotle decided there were in fact 7 colours on a spectrum of brightness after watching the light change across the day from lightness to darkness.

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As an inductivist, he saw knowledge as being learnt from observation or sensory experiences e.g. what you can see, hear, feel, smell and touch.
You can see colours, therefore they are.

Colours in the Renaissance 

Fast forward a few centuries to the Renaissance period where we meet a man by the name of Leon Battista Alberti. A triple-A threat, he was an author, an artist and an architect. 

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LEON BATTISTA ALBERTI


Alberti figured that there were 4 “true” colours and like Empedocles, he associated these with the four elements, however slightly differently.

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Alchemy symbols for air, water, fire, earth.

  • air = blue
  • water = green
  • fire = red
  • earth = grey/ash 

He noted that mixing these colours could produce an infinite amount of other colours. Black and white could be used to either darken or lighten the other colours but were not colours themselves. 


Creating Rainbows with Newton 

This finally leads us into the research of one of the most vital figures in this quick evolutionary history of colour – Sir Isaac Newton. 

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ISAAC NEWTON

Newton had much more science-as-we-know-it-today basis to his colour work in 1666 leading to his discovery of the colour spectrum.

He created an experiment trying to disprove other theories and prove his own – that light consisted of particles instead of waves. 

After darkening his room, Newton left one small ray of sunlight to pour in. He then held up a glass prism in the path of the light and watched.

A rainbocoloured strip of light appeared on his wall.

He then held another prism up and the colours converged to create white light again. 

This refracting (bending) of light that Newton had performed was a big leap for theories of light. However, in terms of colour theories this experiment was also extremely important.

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ISAAC NEWTONS COLOUR EXPERIMENT (VERY SIMPLIFIED)

What was learnt from this experiment?

  1. Newton coined the term “colour spectrum” and divided it into 7 colours; red, orange, yellow, green, blue, indigo & violet (or ROYGBIV as we now commonly refer to it).
  2.  Each colour had it’s own angle of refraction (the amount at which the light ray bends).
  3. No matter how many times you bend that ray of coloured light, it will still be the same colour. 

But most importantly, Newton’s experiment concluded that colour makes up light.  When light falls onto an object, the way in which that light is reflected back, determines what colour our eyes will see. 

And that my friends, is the beginning of colour. 

You can find out more here: