What is the Colour Rendering Index? (CRI)

Answer

• The colour rendering index (CRI), is a quantitative measure of the ability of an artificial light source to reproduce the colours of various objects faithfully in comparison with natural sunlight.

• Sunlight has a CRI of 100.

• Artificial light sources with a CRI of 80 or higher offer a truer light and display all the colours of the light.

• For example, a light with a CRI of 50 recreates only 50% of the colours as they would appear in Sunlight. This is why it is so important to have a CRI above 80!

• Important: A high CRI is useless unless it is combined with Daylight Colour temperature between 6000 and 6,500K. (actually, a normal tungsten bulb has a CRI of 100. BUT as the light is very orange (2,700K), the high CRI benefit is completely lost.