Everything the Artist Needs to Know About Lighting in the Studio - Colour Temperature (Part 1 of 5)

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In this series we look at artificial lighting in the artist’s studio. In the first article we talk about the colour temperature of  lighting.  Colour temperature is important as it reflects the colour cast that a light source projects onto a work.  This affects colour reproduction, but can also enhance or detract from a work.

                 

Last week I had some artist friends around to celebrate my birthday.  When we get together the topics wander, but one of the print makers asked about lighting for reviewing their prints as the days get shorter and gloomier.  Fortunately I was able to show them a day-light corrected incandescent bulb I had bought the day before.

 

As the discussion progressed, I realised that many artists, while knowledgeable in their respective fields, have a limited knowledge of lighting – as my introduction to art was via photography I had assumed that everyone had the detailed knowledge of lighting I possessed.  Not so.  Accordingly I have decided to share the following information in a series of posts – “Everything the Artist Needs to Know about Lighting – and some more besides”

                       

 

There are five main considerations regarding lighting affecting the typical artist in their studio.  These are:

i)                    colour temperature

ii)                   colour spectrum

iii)                 type of lighting

iv)                 position of lighting

v)                  brightness of lighting

 

Colour Temperature

 

Most artists will realise that sunlight close to sunset (or sunrise) is quite yellow or orange in colour.  In contrast, midday sunlight on a cloudless winter day is a bluish white.  Landscape artists will be aware of these changes and how it strongly affects the visual qualities of the landscape.  However, not all will be aware of the technical side of colour temperature, and how it relates to artificial light.

 

The normal scale for indicating the colour of lighting is “Kelvin” (which is also a unit of temperature).  The symbol for degrees Kelvin is “K”.  Essentially the colour of lighting (in Kelvin) represents the colour of light emitted when heating a block of carbon to that temperature.  Fortunately, people have created tables which give an easier indication which most artists can relate to:

 

1900K                         typical light emitted by a candle flame

2200K                         typical light at sunrise or sunset

2600-2900K                typical light by common incandescent bulb

3000K                         typical light by standard halogen bulb

4000-5000K                typical sunlight 2 hours before or after midday

5500-6500K                typical noon sunlight (winter sunlight can be much higher)

5500K                         typical camera flash

7500K                         outdoor shade areas on bright day

7500-10000K              cloudy day

10000-12000K            bright clear winter day with blue cloudless sky

 

It should be noted that Kelvin is not a measure of brightness, but colour temperature (and hence gives an indication of colour cast – the lower the number the more yellow-orange-red the light, while the higher the number the more bluish-white the temperature).

 

For the artist, colour temperature is important as it will alter the colour reproduction of what you are looking at.  Accordingly, it is useful to review or create your work in a colour temperature similar to that in which the work will be viewed, and for this multiple light sources may be desirable to emulate different situations. 

 

For reviewing and proofing work, colour temperature is not the only consideration with regards to accuracy of colour reproduction – something we shall discuss in the next article of this series.

Most artificial lighting will specify a colour temperature on the package, though most standard incandescent bulbs will fall within the range above (incandescent bulbs don’t generally state colour temperature on packaging.  Personally I like to work in a colour temperature range of around 2800 to 3500K.  However for proofing I will use a daylight corrected incandescent bulb – unfortunately most manufacturers don’t specify the colour temperature, but research suggests they are typically around 3800K.

 

Remember also that a light source near a strongly coloured wall will affect the colour temperature of light in the studio.  Light bouncing off a white wall will be quite different to that bouncing off a red wall.  Hence consider the positioning of your light sources in relation to coloured areas of the studio, as well as the colour temperature of the light source itself.

 

Also the artist should be aware of the effect of colour temperature when photographing works – not everyone is able to afford or access the services of a professional photographic setup for fine art reproduction.  Also, the sun and weather are not always co-operative when you want to pop outside to photograph your latest work so you can email it to a gallery.  Colour temperature has a strong effect on film media (with few exceptions, you need to buy a film specific to your lighting conditions).  The effect is just as pronounced with digital photography, though most modern digital cameras have an automatic colour balance (which can be manually over-ridden).  The problem is that the colours of your artwork can upset automatic colour balance, and you may be forced to manually select a colour balance setting which matches the colour temperature of your lighting.  We will look at this more fully in a following series about “Photographing and Reproducing Artwork for the Average DIY Artist”

 

More reading on Colour Temperature - http://www.ephotozine.com/article/Guide-to-colour-temperature-4804

article image courtesy of NASA