Translate this page into:

Welcome!




Welcome to Nolver's Science Corner! If you would like to read my blog, visit my website on Nolver's Cozy Corner. This page is dedicated to people who are into scientific subjects. Don't hesitate to be a member of this page!

For tags, visit my website on Nolver's Pretty Tags, for PSP tubes, visit my page on Nolver's Cool PSP Tubes. For my personal blog, visit my page on Nolver's Room.

**Always scroll down to read the actual post**


©2013-2017 Nolver's Science Corner. Images with my watermark are copyrighted by me, so I reserve all rights. It is not allowed to edit or to modify the pictures in any way. It is not allowed to use the images/backgrounds from the layout and from the welcome box. Please respect my work.

Thursday, January 15, 2015

Are Black & White Colours?



The answer to the question - "Are black and white colours?"  - is one of the most debated issues about colour. Ask a scientist and you'll get a reply based on physics: “Black is not a colour, white is a colour.” Ask an artist or a child with crayons and you'll get another: “Black is a colour, white is not a colour.” (Maybe!)

Colour Theory 1 - Colour as Light 


Red Green Blue 

The question:
Are black and white colours when generated as light?
 The answers:
1. Black is the absence of colour (and is therefore not a colour).

Explanation:
When there is no light, everything is black. Test this out by going into a photographic dark room. There are no photons of light. In other words, there are no photons of colours.

2. White is the blending of all colours and is a colour.

Explanation:
Light appears colourless or white. Sunlight is white light that is composed of all the colours of the spectrum.  A rainbow is proof. You can't see the colours of sunlight except when atmospheric conditions bend the light rays and create a rainbow. You can also use a prism to demonstrate this.

Fact: The sum of all the colours of light add up to white. This is additive colour theory.

Colour Theory 2 - Colour as Pigment or Molecular Colouring Agents

 

alt
 Red, Yellow, and Blue
(The primary colours of pigments in the art world)

alt
 Cyan, Magenta, and Yellow
(The primary colours of inks in the printing industry)



The question:
Are black and white colours when they exist as pigments or as molecular colouring agents?

 The answers:

1. Black is a colour. (Chemists will confirm this!)

Explanation:
Here's a simple way to show how black is made: Combine all three primary colours (red yellow and blue) using a liquid paint or you even food colouring. You won't get a jet black, but the point will be clear. The history of black pigments includes charcoal, iron metals, and other chemicals as the source of black paints.

Therefore, if someone argues that black is the absence of colour, you can reply, “What is in a tube of black paint?” However, you must add the fact that black is a colour when you are referring to the colour of pigments and the colouring agents of tangible objects.

2. White is not a colour.

... but .... in some cases you could say that white is a colour.

The grey area:

Technically, pure white is the absence of colour. In other words, you can't mix colours to create white. Therefore, white is the absence of colour in the strictest sense of the definition. However, when you examine the pigment chemistry of white, ground-up substances (such as chalk and bone) or chemicals (such as titanium and zinc) are used to create the many nuances of white in paint, chalk, crayons - and even products such as Noxema. It's worth noting that white paper is made by bleaching tree bark (paper pulp). Therefore, you could say that white is a colour in the context of pigment chemistry.

The question:
Are black and white colours?

 The answer:

1. Black is not a colour; a black object absorbs all the colours of the visible spectrum and reflects none of them to the eyes.


The grey area about black:

A black object may look black, but, technically, it may still be reflecting some light. For example, a black pigment results from a combination of several pigments that collectively absorb most colours. If appropriate proportions of three primary pigments are mixed, the result reflects so little light as to be called "black." In reality, what appears to be black may be reflecting some light.
In physics, a black body is a perfect absorber of light.


2. White is a colour. White reflects all the colours of the visible light spectrum to the eyes.


In conclusion
The colours we see are simply a degree of how much of this colour present in light is reflected. To be completely accurate, a colour reflects the wavelengths in the NM range that our retinal cones respond to.

The medium is the process of reflection of the wavelength of the colour.
The receiver is our eyes which receive the wavelength of the colour.

So, based on the explained theories above, there is one remaining question: if black  is not a colour because it absorbs all colours, why are black people referred as coloured and white as non-coloured??


Source: http://www.colormatters.com



9 comments: