What is the CRI?

Not many people know much about the Colour Rendering Index or CRI but we’ve all experienced the effect of it. Have you ever experienced lighting that gives off a blue, green or yellow tone that is far too much and the resultant glow appears to make all other colours look wrong. Yes, the sort of lights you find in public toilets, offices and shops.

These sorts of lights are early LEDS ad fluorescents and they have a low CRI score. Thankfully, modern lights have greatly improved and now colours are crisper and more accurate. The key is to choose a bulb that has the best rating for your needs and a fitting that matches and enhances the colour. For lighting accessories like Ceiling Roses, visit a site like https://www.creative-cables.co.uk/2648-ceiling-roses

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The CRI is a scale that goes from 0 to 100 and it rates artificial white light’s ability to display colours. The highest score is 100 and it means a light that is able to display colours in the most accurate way, as the colours would appear in pure natural daylight.

A score above 90 offers exceptional colour display almost as good as it would appear in natural light.

Between 80 and 90 is the score that most modern LED bulbs will render colours at, which is still an accurate display of colour.

A score that falls below 79 will mean light renders colours far less accurately to the human eye. Anything below 50 will be clearly inaccurate.

How does colour rendering work?

The colours that we see are as a result of the visible light spectrum. White light comes from the sun and this white light actually contains green, blue, yellow, orange, red and violet wavelengths. When the sunlight bounces off an object, that object absorbs the colour waves and bounces back any that are not needed. These bounced back colour waves are what renders a colour on an object and what us humans see with our eyes. An example is a tree leaves that we see as green. Green is the colour we see because the tree absorbs all of the other coloured wavelengths.

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A lightbulb with a good CRI score has all the same wavelengths as sunlight, or as close to it as possible and that is why the colours appear more accurate. Today’s bulbs, like halogen and incandescent generally have a very high CRI score. It took a while for LED bulbs to catch up as there were issues with the infrared part of the spectrum. LED bulbs are now an excellent choice for home use and often have a score over 80 that is perfectly adequate.

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