COLOUR TEMPERATURE

Yes, colour can also be measured as a temperature and not just labelled as a colour. Last month I discussed ‘the hour of power’, that golden hour of light around dusk. Well this also has a general colour temperature. Basically a cold black ball is slowly heated and changes colour from orange to red to white to blue then white. The colour it expresses at a certain heating temperature and expressed numerically in degrees Kelvin.

Why might this be of any relevance to you? Light sources are also measured in degrees Kelvin. Daylight is about 5500 degrees Kelvin. Your electronic flash is also about the same, thus flash is daylight balanced. Sometimes I hear people asking why everything looks orangey red when they shot indoors without a flash. This is because tungsten lights are about 3200 degrees Kelvin. Cloudy days produce a bluish cast because the temperature is anywhere from 7000-10,000 degrees. Can you see the pattern forming? Lower temperatures produce the oranges and reds while the higher temps produce the bluer hues.

Filter correction is one way of correcting for tungsten or fluorescent light sources. Another way in this modern age of digital is to let the auto white balance in the camera figure it out (though not always accurately) or tell the camera itself what light source you are shooting under.

Sometimes lower colour temps can enhance the image. Who doesn’t like a pink or red sunset?