Thursday, November 29, 2012

How we can see colors?


We all noticed that night, it is difficult to distinguish colors from each other.
It is said that "the night all cats are gray." It is true, the night colors all look
the contrary, when the sun shines, the shades and nuances of color stand each other perfectly.
Our perception of color is due to the light!

Artificial light, if the illuminating an object with a spot color, the color of the object will be modified since
it will color the color of the light spot.

But how happens it?

Initially we sunlight is white.
In physics we learn that if we pass a beam of light through a crystal prism, the light is divided
into a variety of colors called "solar spectrum".

We can see three main colors:

red
green
blue

whose mixtures give us three other colors for a total of six.


red
yellow
green
cyan
blue
magenta

Comment: These six colors add some theorists indigo which is a kind of dark purple!

The rainbow 
can observe the phenomenon of decomposition of light over an arc-en-ciel:

 


In the case of the rainbow, the rainbow, the spectral colors are separated but gradually merge with each other, 
so that there is not only colors but six infinite shades of the eye humans perceive more or less 
well, depending on the "education of the eye

But how can I receive a red object and distinguish it from a blue?




What happens when we see it in a vase saying he is blue, a flower, telling us it is yellow, etc. ... The material of each object receives light his way. Thus we see that vase absorbs blue light parts that give red and green then reflected in the blue space. It is this that our eyes perceive. Similarly for the yellow flower which absorbs blue and reflects red and green mixture which gives the yellow, which makes us say that the flower is yellow.

In nature we can consider that the number of shades of color is infinite.
sensitivity and education of the eye and the gaze, analysis, allow us to increase the number of shades of color
that we are able to distinguish or differentiate.

The computers that we use today allow us to display over 16 million colors.
Below this number of colors an image will leave visible defects appear under a color professional
or any knowledgeable person.