The Effect of Light on Colour

Pay attention to lighting when choosing paint colours… 

By Tammy Adamson-McMullen

If you’ve ever painted a room in the perfect colour only to have it look less than perfect later, the problem may not have been with the paint, your original paint sample or your application. The real culprit could have been your lighting. 

The effect of lighting on colour is something we tend to ignore when selecting paint colours. But the simple fact is that there is no colour without light. And because of this dependence, how we see paint colour is affected by many factors, including the amount of natural light and artificial light in a room.

In general, when there is a lot of light in a room, colours appear more vibrant and saturated; when there is less light, colours dull and lose their intensity. Working together, natural and ambient light can help you achieve truer colour. But first, it’s important to understand the characteristics of these different light sources. 

Natural Light 

Natural light changes throughout the day and is affected by the position of the sun, the seasons, the weather and the location of your home. It also is affected by the location of rooms within your home. Here are a few points to consider:

  1. Natural light in north-facing rooms is cool and bluish. Colours take on the same tint and appear less saturated. To achieve truer colour, add artificial light sources, using halogen or daylight bulbs (see below). If you want more saturated colour, select a brighter paint hue.

  2. The opposite is true of south-facing rooms. Benefiting from more light, especially as the sun peaks in the sky, these rooms bring out the best of both cool and warm colours. Achieving true colour is easier here.

  3. East-facing rooms tend to be warm and glowing in the morning as the sun rises and cool and shadowy as the sun recedes. Colour selection is tricky, as colours will appear more vibrant before noon and duller as the day wears on. Artificial lighting can help, as can blinds, roller shades and other light-controlling window treatments.

  4. West-facing rooms present even more challenges. These rooms can be cool and bluish in the morning, warm and glowing in the afternoon and blindingly brilliant by end of day—and colours follow suit. Artificial light sources and light-controlling window treatments are a must here.

Regardless of a room’s position, you can increase its natural light by tying back draperies, choosing sheer window treatments over heavier fabrics, installing glass-paneled doors, adding mirrors to reflect the light, and trimming back any outside vegetation that might be blocking the windows.   

Artificial Light

Artificial light can play havoc with colour because its effect varies so much from one light source to another. One reason why paint colours look so different when you get them home is that paint stores tend to have fluorescent lighting, which gives off a blueish-green tint. Meanwhile, your light sources at home are probably incandescent, halogen or LED, and each of these has a completely different effect on colour. Here are the distinctions:

1.     Incandescent lighting typically intensifies warm colours—such as red, orange and yellow—and dulls cooler colours like blue. However, bright white and daylight bulbs, which have a higher kelvin number, are a bit cooler in colour. The higher the kelvin number, the cooler the colour temperature of the bulb; so 2500K bulbs are warm in colour and appear yellowish, while 3500K bulbs are a bit cooler and appear bluer.

2.     Halogen bulbs are truer to natural light. Consequently, colours appear more vivid and closer to their true form.

3.     LED lighting can make colours appear cooler or warmer, depending on the bulb you select. Available options are daylight LEDs, which mimic natural light and have a colour effect similar to halogen.

It’s especially important to add a lot of artificial light if you plan to use a dark paint colour, since dark colours absorb light. Keep adding until you’re satisfied—or choose a lighter hue.


Hopefully, this information will help you come closer to your desired paint colour. Still, you can’t neglect the most important step in colour selection: Sampling! Be sure to obtain a large colour sample from your paint retailer—or paint one yourself—and put it up in the intended room where you can observe it in different natural and ambient lighting conditions. If the colour doesn’t meet your satisfaction, go back to the paint store and try again. The good news is that paint colours are nearly infinite. So with a little more experimentation, you’ll undoubtedly find one that makes you happy and in every lighting condition.