Roughly how many colours are there?

Answer 1

Infinite number. Even if you are just considering the visible spectrum, even a fractional difference in wavelength will produce a new color. The human eye can't discriminate all of these (I know mine can't), but they exist nonetheless. Thus, we should also consider the non-visible spectrum.

The selection of red, green, and blue as primary colors is completely arbitrary and could as easily be three different colors. These colors hold no special distinction in the physical world.

Answer 2

Officially the only true colours [colors] are those which appear in the light spectrum, which can be seen in a rainbow.

Itchy Animation - Light Tutorial White light from the sun is made up of a continuous spectrum of colours which, ... (I'm just using the primary colours, rather than the full spectrum here, ...
http://www.itchy-animation.co.uk/light.htm

BBC NEWS | Technology | Artificial muscles light up TVsLast Updated: Monday, 21 August 2006, 07:49 GMT 08:49 UK ... They manipulate light to reproduce the full spectrum of colours on screen, impossible using ...
http://www.news.bbc.co.uk/2/hi/technology/5263108.stm

TASI :: Advice | Creating Digital Images | Colour Theory ...The particular tinge a "white" light has is described as its colour .... Firstly, certain wavelengths can be subtracted from the full spectrum (by being ...
http://www.tasi.ac.uk/advice/creating/colour.html


What makes red paint red? The chemical make up of the paint reflects the primary red colour when exposed to sunlight and this is why we see it as red.

Obviously it's much more complicated than I have tried to explain above.

As to the total number of colours, I imagine these are virtually unlimited. Certainly in nature there is a riot of colour. Go into any well maintained garden of flowers and see the effect of man working with nature.

Answer 3

There are an infinite number of colours. Colour space is three dimensional.

Hue - The "colour" based on the colour circle (Red orange yellow green blue violet"

Chroma - How pure the colour is Pink -> Red

Saturation - The amount of black or white in the colour.

If you find this hard to visualise, play with the customise colours in MSPaint.

It is also visualised in the Munsell colour tree

Primary Colours

There are two accepted trios of primary colours:

Additve (Mixing lights eg TV Screen)

Red Green + Blue (RGB) (Look at you PC screen through a magnifying glass)

Subtractive (Mixing colours)

Cyan Magenta Yellow (YMC)(look at a colour photo in a magazine)

(Note to improve colour density in printing black is also used (YMCK)

Answer 4

I know you're not going to like this answer, but....
an infinite amount.
Technically, there are only seven COLORS: (red orange yellow green blue indigo violet) but there are infinite shade combinations between all those colors, shade levels, stuff like that. Because the light spectrum is a continuum, there can't really be a set number of colors.

If there were an even distribution of colors when making a new color, technically there would be 960,799 (7^7)+(7^6)+(7^5)..... etc. But that doesn't even account for, you know, 1/3 blue, 1/3 violet, and 1/3 yellow. So infinity, basically.

Answer 5

Time for a cop-out catch all answer.

There are as many colours as there are variations in the wavelength of a photon within the range of visible light. This would not be infinite as there would be quantum 'ceiling'.

A clever person that myself could probably work out where this ceiling would be, and from there the maximum amount of possible colours.

And to that variants by adding black and white, again with a quantum ceiling and you've got a lot, but never infinite.

Answer 6

My computer monitor can mix the intensities of the red, green and blue crystalline 'phosphors' in 4096 increments of intensity, each, for a total of 6.87*10^10 colors. With today's technology it is very possible to increase that number to 2.8*10^14 or beyond.

The human eye is probably not that sensitive, though, so your question may be better asked, "how many colours can the human eye see?" That would define how many colours there are.

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Answer 7

In the 1960 edition of the book, "Psychology'' by Professor J.P. Guilford, it is stated that a normal human eye can distinguish about 340,000 different colors.

As per the book, no one has yet given manes to the 34000 colors. Our language contains only about 300 words that may be used to describe colors. The average man's vocabulary probably employs only a score of those words in every day use.

The artist, painter, the manufacturers of papers, inks and fabrics, feel the great need for communicating with others.

According to Psychology there are two series achromatic and chromatic series.
The first one contains black white and grays. Achromatic means with out colors. In Psychology white gray and black are not colors.

The chromatic colors include all the rest.

The achromatic series extends in a straight line from white at one end to black at the other end. Neutral gray is in the middle. There is a continuous gradation between black and white with no gaps.

A normal individual can distinguish nine definite steps. A good observer can detect as many as 570.

Achromatic series has the common characteristic namely brightness or tint. Nearer to black the lower the tint or brightness.
Chromatic colors also vary in brightness. For example we speak of light blue or dark blue.

Other than the brightness chromatic colors have hue and chroma. Examples of hue are purple orange green violet red blue or yellow. Normal human eye can distinguish as many as hundred hues whereas a good observer can distinguish as many as 160.

The chroma or saturation is the other property. A saturated color is rich or pure. Pale or washed out colors and dull or muddy ones are unsaturated or some what lacking in chroma.

Answer 8

A "colour" is defined as a particular frequency of the elctromagnetic spectrum, in the interval of visible light.

Since the frequency is a cuntinous function, there are infinite values it can assume.

The human eye can usually see around 400 to 700 nm (nanometres), from violet (around 400) to red (around 700).

your question is like asking how many real numbers (let's say that "real number" means "with comma", like 600.436 or 566.2415, although there is a more rigorous definition of "real number") there are between 400 and 700, and, of course, the answer is that there are infinite real numbers in that interval, hence, infinite colours.

Answer 9

Well with the adevent of 32 bit colour brining some 16.7 million colors, the eye is unable to tell between all othese the alotted in sequence, so the question maybe should be, how many do we as humans need if we cant see them?!

Answer 10

There are only the primary colours the rest are shades.
Black and White are not colours.