Illuminati Creative Technology, Colchester UK

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The poetics of Stage Lighting: A Zen approach to theatre technology COLOUR- The inside facts about Colour page1

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It is a tool for evoking emotional responses that trigger people to behave in certain ways .

It is a window on the soul, a bridge to the interpretation of the indescribable in human experience, a means of expressing feelings and the intangible.

It is a thing of beauty and a determinant of survival in nature

It is a way that painters and lighting designers can cause an emotion to sweep like a hurricane through an audience - or kill it stone dead.

It is a subtle manipulation tool which can change the way we feel, the way we react, and the way we make decisions

It is inextricably linked with our culture and our early conditioning

 It works the most basic level of perceptions of all - the emotions- without needing to go through any kind of intellectual process on the way.

It is: sophisticated, subtle, evocative, inspirational, elusive, complex,


The development of civilisation brought with it the urge and the ability to represent not only the objects of the natural world, but those of dreams, imagination and religious aspirations

Asked “what is your favourite Colour?” , Cezanne replied “ Blue? Green?  The hot ochre of the Bibemus Quarry?  No. For colour to work, for forms to thrive, for objects to come together and excel themselves, the artist has to succeed in reconciling general harmony


Electromagnetic radiation is the transmission of energy in the form of waves having both an electric and a magnetic component. It is not possible for a wave with just one of these components to exist.  The most familiar forms of electromagnetic radiation are radio waves, light waves and x-Rays.

            The visible spectrum occupies only a small portion of the range of known electromagnetic waves, which includes infrared, microwaves, and radio waves (all of which are longer than light waves) and ultraviolet, X rays, and gamma rays (which are shorter).

            In principle, the electromagnetic spectrum extends from zero, the short wavelength limit of the gamma-ray end of the spectrum, to infinity, the long wavelength limit of the radio end of the spectrum.

             The amount of energy contained in electromagnetic radiation varies with its wavelength. At the radio frequency end of the spectrum the power  is  comparatively weak . As we move further up the spectrum, the power increases until we get to the fierce searing power of nuclear fission and gamma rays.

 Electrons in atoms have several energy levels; they are normally found in the lowest, the ground state, but when energy is applied to them, in the form of light, heat, or for that matter mains electricity, they may be excited into an higher energy level. However, this higher level is unstable; this means that the electron cannot stay there, and must give up the extra energy in order to return to the ground state, emitting it in the form of a photon.

            An electron can only accept a specified amount of energy (the reason involves quantum physics, and I really don’t want to get into that here), and release the same; this amount is different for each element. Since energy is proportional to wavelength, and wavelength defines colour, then the colour of the light  depends upon the substance excited, and upon the amount of energy  supplied to excite it. As an example, a 70 watt low pressure sodium lamp (SOX) will glow monochromatically in a murky yellowish colour,  whereas a mercury lamp of the same power rating will glow with a bluish-violet hue.

 It should not be assumed that light produced in this fashion is always of only one narrow wavelength; that would require not only a completely pure sample, but a perfectly precise and evenly applied amount of energy, which is to all practical purposes impossible.

            In the visible portion of the spectrum, the various colors perceived by the human eye correspond to wavelengths ranging from about 0.0004mm  (400 nanometers) (Violet), to about 0.0007 mm.(700nm) (Red).  The various colors of the spectrum fall between these limits.

            The perceived colour of an object depends not on the wavelengths absorbed, but on the wavelengths reflected, since it is those which reach the eye. An object which appears red reflects only red light (but remember that “red” covers a comparatively wide range of wavelengths from 700nm up to about 750 nm. This accounts for the subtly different shades of colour that can be seen in the  swatch books of red gel, rather than a vista of  uniform red).

The Louvre has recently spent some £30,000 to re-light the gallery in which the Mona Lisa is kept. Using fibre optics to eliminate some of the harmful radiations which can damage the pigments, they have achieved a nice flat even light , a beautifully perfect  colour rendering index and just the right    amount  of lux.....

... So what’s wrong with it ?

 Well,  its just that Leo  da V. probably painted it in a hot Florentine sun with a high preponderance of reds and golds in the spectrum and then went to a hell of a lot of trouble to paint cool tones into it so that when it was viewed by candle light it looked the way he wanted. That’s why, to my eye she looks, La Giaconda,  a bit of a cold fish.

And of course at the Louvre they are, quite rightly,  paranoid about conservation and so the light levels are set to the recommended 180 lux for 8 hours maximum per day. Candle power gives a lot less than that, but looks brighter. (more about conservation lighting)

Why? Well its to do with the way the eye works.


 The eye has  three distinct and separate ways of controlling light. The first is the well known method of shutting your eye: which you can do lightning fast and under unconscious reflex control: the “Blink Reflex”, which can prevent retinal damage, even in some quite extreme situations.

The second is by varying the amount of light entering the eye by opening and closing the Iris. In a healthy eye, this gives a light control ratio of about 50:1. Considering the ratio of comfortable light intensities in nature approaches 50, 000: 1,  that doesn't seem quite enough to allow us to cope with the extremes of bright sunlight and night vision.

There is a third control mechanism: It is called “The Bleaching of the Visual Purple”.
The Receptors in the eye which deal largely with black and white, the “Rods” contain a chemical messaging agent called Rhodopsin. It has the characteristic that the more light you pile on to it the more opaque it gets.
In very bright lighting conditions, although the actual amount of light falling on the retina is not altered,  the rods bleach out and the amount perceived is suitably controlled. In very dark conditions, the eye adapts to the dark and the rhodopsin clears completely.

Back to our candle.......

In the relative dark of a candle, the actual amount of light the brain ‘sees’  is very high. Couple that with the interesting fact that other chemical mechanisms in the human body react in the dark to put you into the mental combination of “relaxed but mentally alert” with adrenaline supplies on standby, you can see that you could be in a very different frame of mind when you view the Mona Lisa.

In fact colour and light has all sorts of chemical and physical effects on the body, most of which we can only guess at. There is a physical disorder called Seasonal Affective Disorder (SAD) which is caused by insufficient exposure to sunlight and can be treated by regular exposure to full spectrum fluorescent tubes. (I tried to get my Doctor to send me to the Bahamas on the National Health Service, but no dice). There is no doubt that sitting in the sun can increase your feeling of well-being, and this is all to do with light spectrum as well as warmth.

We talk of “warm” and “cool” colours. Obviously we associate red with  flames, with the hot eye of the sun, and by inference with danger, warning. Steel blues  and whites with  a low proportion of  reds, we associate with the icy wastes of the Arctic, with the hard sharp rays of the cold winter sun, a clean, sterile environment where very little can live, and therefore Hospitals, work surfaces and refrigerators use whites and pale blues.
Green we think of the coming of the spring and the fruitfulness of the falling rain, and in the winter, the evergreens remind us that better weather cannot be far away.

We even use colour as a badge of membership to various groupings (True Blue, the Reds under the Bed, You’re Yellow! The Green Party) and to social classes:  Purple (The King or Emperor),  Scarlet (Cardinals, prostitutes). Deeper and more saturated colours are generally regarded as a sign of expensiveness and quality whereas thin colours and brighter hues, unsuitable and clashing colour combinations are generally and stereotypically regarded as the province of the “lower orders”.

Some colors or combinations of them irritate eyes and cause headaches. For example, bright yellows—either on walls or as the background on a computer screen—are the most bothersome colors and are not calming or relaxing in any way. Bright colors reflect more light, so yellow over-stimulates our eyes, causing strain and even irritability. You might not want to paint a baby's room in black and white stripes, but you could certainly use it on important signs to attract attention.
Other colors can alter how or what we eat. Blue is known to curb appetites. Why is this so? Blue food doesn't exist in nature, with the exception of the blueberry. There are no blue vegetables, and hopefully, if you encountered a blue meat, you certainly wouldn't eat it. Because of this natural color deficiency, there is no automatic appetite response to anything blue.

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