Light is a natural phenomenon that stimulates sight and allows objects to become visible.
The amount and quantity of Light can determine the ambience of an area and therefore the mood of the setting and consequently the mood of those in that area.

Lighting

Lighting is the general term given to the equipment that produces the Light – in general called Light Fixtures or Light Fittings or Limieres.

Light depends on not only the Light Fitting, but also the reflective areas and properties of the surfaces that are being illuminated.

Light reflects best from light colours such as white on the other end of the  spectrum, black surfaces have minimal or low reflective surfaces as they absorb Light, so the same room with the same Light Fitting with white walls will be far brighter than the same room with the same Light Fitting with navy blue or burgundy coloured walls.

The ceiling in a room is usually the most important reflective surface and for maximum luminosity should also be white were possible.

When choosing a Light fitting; besides looking at the Light source (the type of Bulb and it’s power) one should look at the beam angle and the achievability of that beam angle – Putting a wide beam angle bulb in a full sided metal shade would restrict the angle of the beam and thus the area and distance to where the Light could travel.

So when considering a Lamp Shade around a Light source, one should consider the material from which it is made and the extent to which the Lamp Shade is translucent.

In some areas it is desirable to restrict the beam angle and concentrate the Light in one direction – This is Task Lighting as used in Spotlights, Reading Lights and Work lights such as Pendant Lights over a kitchen island.

Do not make the mistake of thinking that the Light from a Glass Shade is only emitted from its aperture, or that a Glass Shade pointing Upwards only sends

Light upwards – It is glass and emits Light through all of it’s translucent surfaces. In fact shades pointing upwards help the Light Bulbs to dissipate  

It is interesting to know that in general we use Lamp shades for aesthetic properties, whereas in the olden days Light Shades were devised as Shades to protect and shield the naked flames of candles, gas and Oil Lamps from the rigors of drafts and the wind.

There are many different types of Light Fittings; we can classify them into Interior and Exterior products.

For Interior Lighting we have Ceiling Fittings that are Flush, Semi Flush, Recessed, Pendant or Chandelier (multi arm).

For the Walls we have Flush, Recessed and single or multi arm Wall Brackets.

For our Tables we have our Table lamps.

For the Floors we have Recessed and Floor Lamps.

For Exterior Lighting we have Soffit (under Porch) Lights that are Recessed, Flush and Pendant.

For the Walls we have Flush, Recessed and single arm Porch Lights.

For the Ground we have Spike, Ground Buried and Post Lamps.

Now all these Lumieres can have varying Light Sources, ranging across Incandescent, Halogen, Fluorescent and LED each of which giving a different level of efficiency, durability and luminosity.

Light Bulbs

An Incandescent Light Bulb is one in which the Light is produced by passing an electrical current through a wire filament causing it to heat up to a high temperature until it glows.

A Halogen Light Bulb is an incandescent bulb that has a small amount of the chemical iodine or bromine added to it, a halogen cycle is produced of depositing tungsten that has evaporated back onto the filament, thus increasing the bulbs life, maintaining the clarity of the glass envelope and hence can be operated at higher temperatures resulting in a higher luminous intensity and colour temperature. The small size of the Light Bulbs permits their use in compact areas and lend itself to promoting the design of Light Fittings with smaller Lamp Shades.  Retrofit Halogen Light Bulbs are available in the same popular sizes as Incandescent Light Bulbs.

Low Voltage Halogen Light Bulbs require a Transformer to operate and have a greater luminous efficacy, colour temperatu

re and durability than Mains Voltage Halogen Light Bulbs. A 50 watt  Low Voltage MR16 Dichroic Bulb will generate 30% more Light than a 50 watt Mains Voltage GU10 Bulb.

Fluorescent Light Bulbs are low pressure gas discharge lamps that use fluorescence to produce Light, they need a ballast to operate and are more efficient than Incandescent Light Bulbs, but the initial cost is greater. They run cool, so in UK climate your central heating thermostat would come on sooner than if you were running the alternative Light Bulbs which all generate heat. Fluorescent Light Bulbs are hazardous waste as they contain mercury, they take time to warm up and suffer degradation throughout their lifespan.
Retrofit Compact Fluorescent Lamps are available in the same popular sizes as Incandescent Light Bulbs.

Led lamps are a compilation of Light Emitting Diodes assembled as a chip into a Light Fitting or a Light Bulb. LED is the Light source of the future and the technology is moving at great pace. They are small and compact and as the wattages creep up they have the need for heat sinks to dissipate the heat generated. The life span and electrical efficiency is several times better than alternative Light Bulb Sources.
Retrofit LED Light Bulbs are available in the same popular sizes as Incandescent Light Bulbs.

Luminosity for our purposes is the measurement of the quantity and intensity of the visible Light.