Colour Rendition! – how well is that object being lit up, or more accurately am I seeing the true colour.

A quick explanation – the light we see as “white” is a mixture of light of different frequencies – quite literally every colour of the rainbow – red orange yellow green blue indigo and violet. An even mixture of these wavelengths will combine and look white to our eyes.

A handy tool to remember the colours – ROYGBIV that comes to mind every time – “Richard Of York Goes Bathing In Vinegar”  – try googling that! …

We see the colour of an object accurately so long as the corresponding wavelength is part of the incoming light beam. Note that in viewing an object (say an nice bright red) we see it as red because it has absorbed the other colours and reflects the red part of the spectrum back into our eyes. If the illuminating light (lets say it is direct sunlight) is full spectrum, then the red will appear suitably vivid. If the illuminating light artificial then the red part of the spectum may be less intense, then the object we are viewing may not look as vivid – perhaps a little dull for a red, and even when we really look hard perhaps even a little brown.

Note that an object will appear white to us because nearly all incoming light is reflected back. Objects appear black to us because nearly all incoming light is absorbed by that object – for example the keyboard on your computer, with very little being reflected so you can see it.

Artificially created light (electronically created such as LED and florescent, rather than from lots of heat – ie: incandescent and halogen globes) does not always cover the entire spectrum evenly. There will be sections of the spectrum where the intensity will be less than other sections, so if those sections correspond to the colour of the object you are observing you wont see it in its full glory! This is particularly noticeable when viewing artwork.

Colour rendition is describes as a Colour Rendition Index or CRI. CRI of 100 is “perfect” full spectrum. anything less that that will be a compromise. For LEDs and florescent, colour rendition can be quite an issue.

Most of us can relate to going to the bathroom first thing and looking in the mirror… and getting quite a shock… few of us wake well.. There is an additional reason why you might look flat, particularly if you have a florescent of LED vanity light. Flesh tones particularly need good full spectrum lighting to look their best. So if you are not impressed with the way you look first thing, try changing the lighting!

In conclusion, quality does matter when it comes to light sources, and seeking out globes or fittings with CRI of 85 or better will ensure a better ambiance. There is a lot more to say on these subject…Watch this space!