Lighting and bulbs explained

Get to grips with these terms, technicalities and options before you buy our lights and bulbs.

Lighting and bulbs explained
When it comes to choosing the right lights for your rooms – and the right bulbs for your lights – there’s a wealth of information to weigh up.

From direct and indirect light to lumens, wattage and beam angle, we’re here to help demystify the details.

Direct light 
This type of light is focused on one specific area or object and creates an obvious distinction between light and shadow.  

Indirect light 
Indirect light, by contrast, is used to illuminate a much broader area. Shadows are less distinct, and the beam will be evenly distributed around the room.  

Task lighting  
A light source that brightly and precisely lights up one area to provide great visibility. It’s typically used to aid tasks like reading and food preparation.  

Ambient lighting  
Ambient lighting mimics the effects of well-dispersed natural light. It’s generally used in living rooms, dining rooms and bedrooms, and will fill the space with an even, comfortable level of light.  

Accent lighting 
Less overtly functional than the other two types, accent lighting is used to highlight architecture, furniture, artwork and the like. It’ll draw the eye and create impact easily and effectively.  

IP rating 
Lights are given a numerical Ingress Protection (IP) rating so you can tell if they’re safe to use around dirt and water.  

The first number refers to dirt, dust and other solid objects, and the second to water. The higher the numbers, the better the level of protection.
We offer a curated choice of shades for our lights. Each one is made from a different material which will alter the type of light that’s emitted.  

Fine porcelain  
Our fine porcelain shade, meanwhile, offers the mellowest, most atmospheric glow with absolutely no glare.

Solid brass 
Our solid brass shade will aim all the light directly down, so it’s best used when you want your light source to cast a focused beam.  

Fluted glass  
In contrast, a glass shade supplies 360-degree lighting. Ours has vertical grooves that help to diffuse the light that’s emitted.  

Available with our Malvern wall lights, our contemporary 100% linen shade will add texture and contrast. Both the Basalt Grey and Alabaster White colourways will soften the light too. 

LED bulbs give off light using light-emitting diodes. When an electrical current passes through a microchip, the diodes light up. 

LEDs produce light up to 90% more efficiently than incandescent light bulbs and 80% more than halogen bulbs. They cost less to run, produce less heat and last much longer (up to 20,000 hours of use).  

A unit (lm) that’s used to measure a bulb’s visible light output (or, technically speaking, its ‘luminous flux’). The higher the lumen rating, the brighter the light will be.  

Wattage (W) is the unit describing a bulb’s energy consumption (not its light output). Some fixtures, like dimmer switches, have specific load ratings measured in watts that need to be carefully followed.  

Equivalent wattage 
If you’re replacing a conventional bulb with an energy-saving LED, the wattage can’t be matched like-for-like. That’s because LED bulbs don't consume anywhere near as much energy, so their wattage is lesser. 

If you’re trying to match the brightness, you should compare lumens rather than wattage.  

Let this conversion table help you on your way.  
Voltage (V) is the amount of pressure needed for a light to illuminate. Standard mains electricity in Europe is 220-240V. Almost all lights (including all our designs) will work with this voltage.  

Beam angle 
Beam angle measures how light is distributed – or in other words, the angle at which the light spreads out from the bulb.  

A narrow beam angle provides directional light, while a wide beam angle will offer softer, indirect light.  

Colour Rendering Index (CRI) measures how well colours are represented under an artificial light source versus natural light. 

It ranges from zero to 100. At zero, all colours look the same, and at 100, the true colours are easily distinguishable and fully saturated. The higher the CRI, the better the bulb’s colour rendering capacity is. 

Our 50mm Chester and Arthur bulbs have a CRI of 92, which means they’re a really great choice for lighting artwork, expensive paint and so on.  

The Kelvin scale measures the colour temperature of the light. The higher the number of Kelvins (K), the cooler and whiter the light will be. 

We use 2700K for all our bulbs because it provides a really nice balance between atmospheric and functional light.  

G9 capsule bulbs are small but bright. They have two looped pins spaced 9mm apart that push into the light fixture for easy installation. G9 bulbs operate at European mains voltage.  

GU10 spotlight bulbs have two short, squarish pins spaced 10mm apart and have a ‘push-and-twist’ type fitting. Like G9s, they operate at European mains voltage.  

All Corston electrical products should be installed by a qualified electrician.