Lighting Your Garden for Maximum Effect with Aurora

Paul Davidson of Aurora Lighting looks at the benefits of a cohesive and designed lighting installation rather than just installing lighting equipment. This will help provide an area that can improve people’s mods or alter perceptions in subtle words. Energy and glare can be reduced at the same time.

Lighting in gardens has, over recent years, become a priority in order to provide the enjoyment of outdoor areas during the times of darkness. Artificial lighting can extend the time during which the benefits of outside areas can be enjoyed, in addition to providing both adequate illumination for safe access and for security.  An extensive investment is not necessary to provide lighting that can reveal the beauty of flowerbeds, trees, shrubs and water features in a highly attractive manner.
 
The basic objectives of outdoor lighting are to promote safe access of the area by illuminating safety hazards, to provide security at night, to enhance the appreciation of the surroundings and to accentuate the beauty of the general scene by illuminating dark areas that may detract from the visual appearance.

Judgement or expertise?

Often a small amount of light can fulfil the desired requirements and the effects may be ruined by installing an excessive amount of illumination.  No attempt should be made to illuminate everything in sight. The desirable balance between the various illuminated areas is a matter of subjective judgement, rather than engineering expertise, with calculations being subservient to the expertise in dealing with this type of lighting installation.
 
The main features of interest, and any route of progress along which visitors are likely to follow, should be selected to provide scenes that can reveal the areas as they progress. The availability of different viewing directions and the practicality of concealing lighting equipment will determine the feasibility of influencing the visitors to follow a predetermined route through the garden.
 
As far as practicable, lighting should be screened from direct view by plants, shrubs, boulders or the like in order to prevent glare. Lighting equipment, not concealed, must be acceptable as part of the scene by daylight. This may influence the type of equipment to be installed, the positioning or spacing of that equipment to maintain the visual quality of appearance in the environment, or the decision to mount fittings on facades to dispense with any intrusive equipment. All lighting and electrical equipment installed externally must be for use in the outdoor environment and installed by a qualified and approved electrical contractor so that it meets the current IEE Wiring Regulations (BS7671:2008 – First Amendment).

Establishing a theme throughout the areas to be illuminated will allow cohesion between the elements in a scene to be achieved. A high key scene may have mainly bright tones with higher values of evenly distributed illuminance, while a low-key scene has mainly dark tones with illuminance variations giving contrast between light and dark.  

Careful use of scale…

The use of scale in perceived sizes of buildings, features and spaces relative to the other forms or to people is important, as artificial lighting can be selective with the scale interpretation of an environment that differs between night and day. An intimate and friendly scale can be created by controlling contrasts of luminance within significant areas, and the spacing of lighting equipment combined with the light produced are perceived as rhythms. Highlights and shadows give effect to a scene and create modelling by the luminous intensity and the direction of light in relation to the form and texture of the surface being illuminated. These are subjective impressions, so their result cannot be measured.
 
…and variation

Interest can be created and controlled by the variation in lighting effects, such as key tones, colour, luminance and modelling, which is provided by the installation of colour changing, dimming or switching equipment operated via manual or lighting control system in which visitors are led to the next important feature by varying the lighting installation. The effect of distance can be increased or decreased by the luminance or colour of illuminated objects, with more informal and less regular installations varying the effects of depth in a landscape. Moreover, the use of silhouettes helps change apparent relationships between objects in a field of view.

Survey, analysis, design and appraisal

In order to provide a basic guide to the development of an outdoor lighting project, a four basic stage development process of Survey, Analysis, Design and Appraisal should be used.

Survey: It is important that the site is surveyed to fully understand the project and a drawing should be made or obtained. Features should be detailed, such as buildings, their height, shape, location, texture and colour in conjunction with built features such as paths, steps, ramps, artefacts, pergolas and seats – as well as natural features like trees, shrubs, hedges, pools, water channels, etc.

Analysis: The need for lighting arises from human activity and it is necessary to discuss a performance brief to obtain the criteria upon which the design can be produced. The major factors to be considered include site conditions, changes in vertical level, security, movement patterns and routes, vehicle routes and access. Subjective considerations such as character, ambience, image, mood and the perceived effect, are critical to the completed installation.            

Design: The basis of all design is human need, perception and response, and a successful design must satisfy the practical requirements of safety and security while, at the same time, satisfying boyh psychological and aesthetic needs. The eye adjusts to ambient light and can be extremely sensitive to a very weak light source where only the minimum of visual information is required. The lighting design is required to function at various incremental levels of minimum lighting for safety and security, general lighting for normal use and special lighting for visual impact and aesthetic appearance. There is no absolute solution to any lighting situation.

Appraisal: A skilled designer can interpret drawings and be able to “see” the visual effect. Lay clients may require assistance, which can be done in many ways – such as demonstrating proposed luminaires, highlighting drawings to illustrate the distribution of light on a given plane, and illustrations displaying impressions of visual effect.        

Using various lighting effects such as uplighting, down-lighting, wall-washing, grazing, accent lighting, cross-lighting, mirroring, spotlighting, moonlighting, silhouetting, step-lighting, floodlighting, shadowing and ground-lighting will allow the creation of a solution that meets with the individual requirements for the application.     

Light Sources

The lamp does not only just provide the illumination; it can also influence the way in which the light is distributed by the optical system and can also provide the colour. The smaller the physical size of a light source, the more accurately the light distribution can be controlled. For that reason, there is a wide range of light sources that can be used for these types of installations, while also being influenced by the need to consider light source energy usage to conserve electricity.

Lighting controls

Lighting control is a very important aspect of any design. The simplest method is to have the lights manually controlled, which assumes the availability of someone to undertake that control (and do it reliably), but the simplest method is not always the best – some sort of automated control may be prefered. Lighting control forms an integral part of most modern lighting installations, whether they be indoor or outdoor and can take many forms from the simple wall switch through to micro-processor control equipment.

Basic lighting control can be in the form of simple time clocks to control operation by time or photo-electric cells to control operation through the lack of natural daylight (sun going in or onset of darkness etc). Scene designed systems offer the opportunity to change the mood of the lighting in respect of dimming, changing colour and intensity to create different scenes that emphasise special features.

Less can be more

As for do’s and dont’s, you can illuminate anything from architectural features to decking to trees, lawns, ponds, fountains, pergolas, patios, paths, etc., but paint a picture of the lighting you wish to install, by looking at the installation in its entirety, rather than just the local feature you wish to illuminate. Less often more, in that shadowing can create the feeling of mystery rather than providing too much illumination, which can look artificial.

Concealing luminaires in order that the light produced is seen, rather than the luminaire itself can be very effective. However, the installation should take account of growing plants and shrubs. Vary the type of light, the beam angles of distribution and wattages in order to create a precise effect. Colour is critical to any installation as it creates superb effect, but do not exceed what is an effect only to make the area look artificial, like a pleasure park.

The use of quality light sources is the key to success, as having poor quality lamps that fail early will ruin the effect just when it is needed. Finally, exterior electrical installations should be undertaken by a qualified and approved electrical installation contractor, who will ensure that all equipment is adequately protected for external use and that all IEE Wiring Regulations are adhered to.

Remember, a well planned and implemented solution will provide much pleasure for many years to come, so shortcuts on design, equipment and installation are to be avoided.

Aurora

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This feature was first published in Wire In magazine, March/April 2012