Lighting : Lighting August 2015 - Vol 35 Issue 4
30 LIGHTING MAGAZINE | August/September 2015 for various design objectives. Any location could become a distinct design project, that is to say, it would involve thinking through how direct light, whether from windows or luminaires, is interreflected within an enclosed volume to generate an ambient illumination, while at the same time its distribution creates an illumination hierarchy, this being an ordered distribution of illumination to express a distinct and readily recognisable design intent. AMBIENT ILLUMINATION Figure 1 shows the entrance foyer of the Australian National Parliament Building in Canberra. The conventional approach to illumination engineering is to consider what are the critical visual tasks? According to whether the class of visual task in this situation is judged to be ‘simple’ or ‘moderately easy’, the recommended maintained illuminance specified in the relevant standard (AS/ NZS1680.1) would be 160 or 240 lux, and it would be assumed that the selected value would be provided uniformly over a wall-to-wall horizontal working plane 700mm above floor level. To provide this illuminance with optimal efficiency would call for a grid layout of luminaires that directs the total luminaire flux onto the horizontal working plane, but it can be seen that in this instance, an entirely different approach has been taken. Indirect lighting has been installed, and the result is a pleasant and thoroughly diffused distribution of illumination creating something of a ‘sky and ground’ effect, and whether it complies with either of the standard values seems to be quite irrelevant. If instead, the lighting standard specified standard ambient illumination values for indoor locations, where this value would be recognised as the overall density of luminous flux that is just Figure 1. Entrance Foyer to Parliament House, Canberra, Australia. As explained in the text, the Australia/ New Zealand lighting standard specifies a minimum illuminance to be provided uniformly on the horizontal working plane, and the efficient way to meet this standard would be to install a grid-layout of downlighters. Fortunately, the designers did not do that, and instead provided uplighting to create a softly diffused light field that gives light at the eye and reveals the surrounding environment, even though it might not meet the standard. MRSE-based standards would open up opportunities for designers who recognise the potentials that lighting offers to devise lighting distributions for various design objectives. DongGuan | China THE HIGHEST COST EFFECTIVE THE WORLD OF FLOOD LIGHT FLOOD LIGHT THE HIGHEST HIGH BAY COST EFFECTIVE THE WORLD OF HIGH BAY 15W/30W/50W/80W/100W/150W/220W/300W Wattage Voltage Efficacy 90Lm/W 120~277V AC 50W/100W/150W/200W Wattage Voltage Efficacy Reflector 100Lm/W Aluminum 60°/120°, PC 120~277V AC We are professional manufacturer dedicatee on OEM and ODM design and manufacture for Branded Lighting Company & Channel Seller of all the world. We provide you the highest cost-effective LED lighting fixtures.
Lighting June 2015 - Vol 35 Issue 3
Lighting October 2015 - Vol 35 Issue 5