The ability of a surface to absorb or reflect the coloured rays of white light determines its colour.
There are many factors that can influence this colour that we perceive, but lighting is one of the most important.
By manipulating the type of light used, the apparent colour of a surface can be changed.
This effect has to be taken into consideration, when choosing a colour scheme that will work.
There are two main sources of light; daylight and artificial light (which includes incandescent and fluorescent light).
Daylight - This varies enormously throughout the day when the angle of the sun changes in relationship to the earth.
This provides different light at different times of the day, and will also change according to where you are in the world.
The weather will also effect the quality of daylight, with a much brighter light being present on a sunny day, as opposed to a subdued light on a dull day.
Daylight can be divided into two main types, of direct sunlight and North light.
Direct sunlight has a fairly even distributed spread of coloured rays, whilst North light scatters the blue short waves, providing a predominately blue light.
Whichever daylight source is used, colours are seen as more brilliant.
Incandescent - This is the most widely used source of artificial light, and is produced by heating a tungsten filament in a glass lamp, by electricity.
There are many forms of incandescent light available, with devices varying in shape, spectral output and lumen intervals, but they all rely on the basic design.
Incandescent light produces light that is loaded into the infrared portion of the spectrum, resulting in the majority that is emitted, being in the lower yellow-red segment of the visible spectrum.
The many lamps that are available produce different effects, with some favouring a yellow light, some a reddish tint and some halogen lamps giving a general illusion of a whiter light.
Incandescent in all its forms provides a good general lighting solution.
For example a room could be painted in blue, and seen as a brilliant blue in normal daylight.
This however, could be seen as a blue-grey colour under incandescent lighting, providing a cold, lifeless environment.
It can also help the appearance of a room, because a green under daylight may appear sterile and hygienic, but under incandescent lighting, it takes on a yellowish tint and appears much more inviting, friendly and cosy.
The aspect of a room will play an important part in how a colour scheme is perceived.
The type of light received in a room will depend on its position.
If a room is North facing - the light will have a bluish tint and appear cold.
If a room is East facing - the light will make the room appear warm in the morning, but cold in the rest of the day.
If a room is South facing - the light will have a yellowish tint and appear warm.
If a room is West facing - the light will make the room appear fairly warm, especially in the afternoon.
In a North or NE facing room, pale blues and greys should be avoided as they can make the area appear chilly, due to the lack of natural light.
Instead warm colours such as red and yellow should be used because they are less light reflective by day, appearing warm and inviting.
When these colours are viewed by incandescent light, they take on an orangey tint, enhancing their warm qualities further.
The cool colours are best used in Southerly facing rooms that receive large amounts of daylight.
These however, can seem less appealing by day, and are enhanced enormously with the use of incandescent lighting.
As shown, the differences between daylight and incandescent light can provide the interior designer with many problems.
It is essential that all aspects of the room's position, usage and environment be fully considered before selecting a colour scheme.
If this achieved then the room will be enhanced regardless of being viewed in daylight or incandescent light.