davelegacy
Member Number 16
how many different colors are there?
Name: Joann
Message: approxamately how many different colors are there. I read somewhere that there are over 16 million different colors.
16 million is an estimate of how many different colors a 24 bit RGB computer monitor can simulate. This has no relevance to how many different colors the human eye can distinguish.
Just as there are infinitely many numbers between 380 and 740 - including all of the fractions, of course - so there are infinitely many wavelengths between 380 and 740 nanometers - the visible spectrum of light. That doesn't even count the different tints and shades obtained by mixing in white, black, etc. So, there is an infinite number of colors, if you look at it that way.
However, that does not imply that the human eye can distinguish an infinite number of colors. If you consider the apparent color of two wavelengths of light, the color will appear to be the same once you get the two wavelengths close enough. How many different colors can the human eye distinguish? The Encyclopedia Britannica mentions that the human eye can distinguish wavelengths as close together as 1 nm apart in the blue-green and yellow areas of the spectrum, but only those 10 or more nanometers apart in the deep red and violet. If the entire visible spectrum, from 380 to 740 nanometers, could be distinguished at a resolution of only 1 nanometer, the total number of spectral colors would be (740-380), or 360; for a resolution of 10 nanometers, it would be one-tenth this, so the total number of spectral colors is somewhere between 36 and 360. However, this does not take into account the non-spectral colors: the different tints which may be obtained by adding white light (or paint), the different shades which may be obtained by reducing the relative amount of light (or adding black paint), and the other non-spectral colors obtained by mixing different spectral colors.
Name: Joann
Message: approxamately how many different colors are there. I read somewhere that there are over 16 million different colors.
16 million is an estimate of how many different colors a 24 bit RGB computer monitor can simulate. This has no relevance to how many different colors the human eye can distinguish.
Just as there are infinitely many numbers between 380 and 740 - including all of the fractions, of course - so there are infinitely many wavelengths between 380 and 740 nanometers - the visible spectrum of light. That doesn't even count the different tints and shades obtained by mixing in white, black, etc. So, there is an infinite number of colors, if you look at it that way.
However, that does not imply that the human eye can distinguish an infinite number of colors. If you consider the apparent color of two wavelengths of light, the color will appear to be the same once you get the two wavelengths close enough. How many different colors can the human eye distinguish? The Encyclopedia Britannica mentions that the human eye can distinguish wavelengths as close together as 1 nm apart in the blue-green and yellow areas of the spectrum, but only those 10 or more nanometers apart in the deep red and violet. If the entire visible spectrum, from 380 to 740 nanometers, could be distinguished at a resolution of only 1 nanometer, the total number of spectral colors would be (740-380), or 360; for a resolution of 10 nanometers, it would be one-tenth this, so the total number of spectral colors is somewhere between 36 and 360. However, this does not take into account the non-spectral colors: the different tints which may be obtained by adding white light (or paint), the different shades which may be obtained by reducing the relative amount of light (or adding black paint), and the other non-spectral colors obtained by mixing different spectral colors.
