Is understanding about beam angles of light soley the territory for the lighting expert or is it really relevant to you? Surely light goes wherever it wants and all we can do is locate a light fitting roughly in the right place?
Choosing beam widths from light sources wherever possible is actually a key principle to understand to elevate your lighting design and transform your interior to a professionally lit space. This can easily be done by anyone with these helpful tips on choosing beam angles for better lighting.
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It would be good to know what exactly a beam width or beam angle is before we can begin to control it. Think of a light source such as LED that creates lots of light, as an eager messenger that simply wants to tell everyone it’s here and spreads everywhere – fast.
The light fixture that light source fits into, whether it’s an LED light bulb screwing into a downlighter or a light fitting with a built in dedicated LED source or whatever lamp and product combination you have, they are all designed to take back control and direct that light out of it as efficiently as possible and with some choices of where the light should go.
How the light or light beam is distributed as it leaves the light fixture it is in is the beam angle.
You can sometimes adapt a light fixture to use your choice of beam angle by selecting the chosen specific lamp or bulb that goes into it.
For example, a mains powered downlighter using a GU10 lamp holder requires a GU10 lamp to twist and lock into it. Your choice of lamp will determine how wide the light leaves the downlight.
All great lighting schemes allow the darks to play a supporting role to the lights and we are aiming to never over light a space. We do this by purposefully choosing where the light should fall by carefully positioning our light fittings BUT it’s how the light leaves the lighting fittings that needs consideration too.
A fundamental lighting design tip is to actually consider where the darkest parts of the room need to be as well as the lightest. It’s our job as designers of our spaces to take back control of where light ends up
Imagine your room as a blank canvass of darkness and we use lighting to sculpt the shadows and use the beam angles from our the lamp or fixture to fine tune how it travels and where it will reflect.
Be purposeful in choosing what you are lighting even if it is just the whole room. Is it an object, maybe some furniture or general lighting.
Do not be tempted to just settle for whatever happens to be at hand and decide how wide the light needs to be to adequately cover what you want to light.
Should it be wide to make a general covering of light or more concentrated and reigned in more tightly to focus in on an object?
By understanding that you can limit where light will go, you are now ready to make your own choices – so what’s an easy way to quickly do that without getting complicated?
Light spreads increasingly wider the further it leaves its source, so how wide would you ideally want the spread of light to go by the time it hits the surface you want to light up?
For example, you have a room you want to illuminate well but you still want to retain some of those important darker bits so you do not want everything lit uniformly. You do this by choosing important elements within the room to illuminate rather than all of it and the right beam width will help in that design.
The amount of light sources and the type of light is first considered. What kind of coverage do you want?
Take downlighting as an obvious example, first ask what does this light need to deliver, does it have a specific role or part of a team of other downlights? On it’s own or part of a pair to say highlight a picture or object then we need to know where the light from these sources will go and overlap. When arranging them in a ceiling to light a room or area, we need to know where their overlap will be so we can estimate how many we need and their spacings.
We need to calculate the distance between the light source – the downlighter – and the surface you want the light fall on – maybe a picture, the floor or a couch?
This will take some care but do not be frightened off by the instruction below to draw to scale. Grab a ruler and make your own scale – say every 1” on your paper is 1ft in reality, or in metric every 2cm is 1m.
Note: you may have a wide surface to be lit and it will be obvious that you need more than one light fitting to do the job otherwise the beam angle you need is going to be very wide.
Here are some typical beam angles and where you would use them:
Use to concentrate the light and deliver as much as possible with the minimal amount of spread. Often used with the smaller in ground and niche lights and typically approximately 15 degrees.
Probably the most commonly used beam angle for interior lighting, this delivers the light with the impression of brightness. Approximetly 26 degrees, this is a go to beam width for a concentrated pool of light that is enough to give a good enough spread of light for an average domestic ceiling height yet retain some definition between the other downlights as long as they are not positioned too closely.
At approximately 44 degrees, this is also a useful beam angle for domestic applications where the wide beam width helps deliver a good covering of light. Wider beam angles say from a downlight, positioned carefully can also illuminate vertical surfaces as well as the objects directly under it, such as a kitchen cupboard door.
A flood beam width is used to very widely spread light across a room. At approximately 54 degrees it creates a useful wash of light yet restricts the light to not go too wide and loose the useful intensity.
A wash beam width is used to maximise spread over the importance of light intensity. Applications like wall washing from a limited number of downlight sources will use an approximately 60 degree wash beam width to spread light across the wall and it’s contents with a thinner layer of light.
Light is also used and chosen to highlight objects along its pathway. The beam angle of the light is important to get right to ensure the right amount of light is getting to where you want it.
If you use a floor light to up light a column, you need to keep the beam width as tight as possible so it illuminates the surface of the column all along it’s path. This will need a tight beam angle from the chosen light fixture.
Choosing a wide spread of light would feel like the best thing to do in most interior applications as you want to spread the light evenly and make the most of the light being created. However, the amount of light delivered is not dependent on the beam angle. The width of spread will determine how concentrated the light is on a surface, so the feeling of brightness can actually be enhanced from tighter beam angles, not wider ones that spread the same amount of light out further.
Another great benefit to purposefully choosing your angles of light is that it also helps combat the glare that light can bring to the eye.
Think of a car headlight at night, we drive with the lights ‘dipped’, meaning the width is narrowed and the angle pointed towards the road. This ensures other drivers are not blinded with the glare off other cars.
You should consider the same thinking for your interior lighting. The wider you make the light, often the greater potential for glare for the users of the space.
Try to not use a wide, wash and flood beam width with directional lighting unless you can ensure the light is mostly directed away from eyes – say onto a wall.
LED is the description of the light source, the light fixture or lamp the LED is in will be designed to direct that light out of it at a specific angle. The widely available common LED GU10 lamp will be a medium beam angle of approximately 36 degrees to suit most applications. Not too wide – not too tight.