Daylight Lighting

About Daylight Lighting

Keeping the impression daylight when it’s dark outside can be very important. There are numerous daylight bulbs types to choose from with one common feature: they are much whiter than ordinary bulbs.

Incandescent (ordinary) bulbs feature a yellow light. Even though our eyes get used to it quite easily, the colours we see differ completely from the ones seen in natural daylight. The easiest way to see this, is to take an indoor photo when the room is lit by an ordinary light bulb and then another one when the daylight bulb is used. The “yellowness” in the first photo can be seen straightaway.
The colour of a light bulb can be measured using a scale known as “Kelvin” (°K).  Lower colour temperatures contain more red light and appear “warmer” whereas higher colour temperatures contain more blue light and appear “cooler”. Standard light bulbs typically have a colour temperature around 2700°K whereas daylight bulbs give off a much “bluer” light at the same colour temperature of natural daylight - around 6000 to 6500°K.

Natural daylight is not just a single colour but contains all of the colours of the rainbow. This range of colours enables our eyes to see things in a natural and balanced way. Light bulbs we choose for our home should give a good balance of colours. This, again, can be measured on a scale of 1 to 100 and is called the colour rendering index (Ra). Light with just a single colour has an Ra of 1 whereas that of natural sunlight is 100.

Benefits Of Daylight-Simulating Lighting

As said above, the daylight bulbs give much whiter light than the standard ones allowing a better-balanced spectrum of light. It means that the colours seen in a daylight lighting are seen more clearly and the objects appear more natural. Another benefit is that most people feel better living in an environment lit by natural lighting and suffer less from eye strain. People that suffer from Seasonal Affective Disorder can find significant relief by using lighting that simulates daylight.

Choosing The Right Lighting

Most daylight bulbs are produced using ordinary bulbs and filtering out some of the yellow light. Even though they give off slightly less light than a normal light bulb of equivalent power rating, they give a more balanced light and hence are good for craftwork. They are both good value as well as give excellent results.

Another types of light that’s similar to daylight are fluorescent tubes. They give out more light for a given amount of power and can be produced in a wide range of colours. Daylight fluorescent tubes can give a very white light, typically at 6000 – 6500°K. Standard daylight tubes however only have a moderate colour rendering with an Ra of around 75.
Tri-phosphor or multi-phosphor light bulbs, which are more specialist fluorescent tubes, give even closer daylight effect. They are designed to give an even better balanced light spectrum and can achieve colour rendering in excess of 80 or even over 90. These are known as “full spectrum” bulbs.
Sometimes it is not practical to use fluorescent tubes. This type of light provides an excellent quality of light with an Ra of around 85 and also give the equivalent light output to a 100W bulb yet consume only 20W.

Here at Commercial Lamps we often recommend specialist yet affordable flourescent tube lighting for inside offices, especially if those offices lack natural lighting or workers are likely to spend long stretches of time inside. The natural daylight effect of the lighting can improve mood, effectiveness and worker efficiency in an office. Don't hesitate to get in touch if you have questions, and we'd be happy to advise you on the best kind of lighting for your situation.