What Lighting Is Best For Viewing Colours Accurately?

Most environments where monitors are used for assessing colour use fluorescent lighting. This can be fine as some fluorescent lighting is suitable for working with colour, however there are certain types that aren't so it's important to know what type of  fluorescent light you're working under.

The majority of fluorescent lights sold to the general public aren't suited for colour work as they have a highly biased light spectra and differences in colour are very apparent when colours on an LCD screen are compared to paper. For example, colours which are accurately printed can appear greenish when viewed under the wrong type of fluorescent light.

Fluorescent lights which are suitable for working with colour are called high colour-rendering fluorescent lamps or fluorescent lights for colour evaluation.

The light spectra of these types of lamps are similar to that of the sun, and there's very little divergence when comparing the LCD monitor screen, printed paper and how humans recognise colour.

The Ra value of the light you're working under is important as the International Commission on Illumination (CIE) recommends fluorescent lighting with a Ra of 90 or above is used in environments where colour is evaluated. Ra is the average colour-rendering index which measures colour-rendering performance (colour rendering describes the colour an object appears to have under a certain light). When lighting is given an Ra value of 100, this means the lighting is identical to that of natural light. 

The problem with these types of lamps is that the majority of them are tubes, which aren't easy to use in a home environment without modifications. When working at home, three-wavelength fluorescent lamps can be purchased. These offer a relatively high colour-rendering performance and are readily available. Take a look at a lamp's specifications when trying to determine if it's a three-wavelength model.

When it comes to colour temperature, the ideal colour temperature for a fluorescent lamp is 4600-5400K (a daylight lamp).

Visit the EIZO website for more information on LCD monitors available from EIZO.