Light Line September/October

The Society of Light and Lighting

LIGHT LINES

VOLUME 14 ISSUE 5 SEPTEMBER/OCTOBER 2021

CONTROL CENTRES A new SLL guide gets to the heart of things

THE BUTTERFLY EFFECT Recreating iridescence

Editorial

September/October 2021

FROM THE EDITOR SECRETARY Brendan Keely FSLL bkeely@cibse.org SLL COMMUNICATIONS MANAGER Juliet Rennie Tel: 020 8772 3685 jrennie@cibse.org EDITOR Jill Entwistle jillentwistle@yahoo.com COMMUNICATIONS COMMITTEE: Linda Salamoun MSLL (chair) James Buck Iain Carlile FSLL Jill Entwistle Chris Fordham MSLL Rebecca Hodge Eliot Horsman MSLL Stewart Langdown FSLL Luke Locke-Wheaton Rory Marples MSLL All contributions are the responsibility of the author, and do not necessarily reflect the views of the society. All contributions are personal, except where attributed to an organisation represented by the author.

COPY DATE FOR LL6 2021 IS 6 SEPTEMBER PUBLISHED BY The Society of Light and Lighting 222 Balham High Road London SW12 9BS www.sll.org.uk ISSN 2632-2838 © 2021 THE SOCIETY OF LIGHT AND LIGHTING The Society of Light and Lighting is part of the Chartered Institution of Building Services Engineers, 222 Balham High Road, London SW12 9BS. Charity registration no 278104

Printed in UK

2

Unit C, Northfield Point, Cunliffe Drive, Kettering, Northants NN16 9QJ Tel: 01536 527297 E: gary@matrixprint.com

The romantic poet John Keats once denounced Isaac Newton because he had 'Destroyed the poetry of the rainbow by reducing it to a prism'. Richard Dawkin, who of course borrowed fom Keats in naming his book Unweaving the Rainbow, sought to show that there was infinitely more poetry in the understanding of science, that its exploration could only deepen the sense of wonder evoked by phenomena such as the rainbow.

The discussion could well be continued in the context of another discovery in the sphere of colour and light, that of how to recreate the iridescent colours found in nature (Reflected glory, p9). Researchers at the Oxford-based Lifescaped lab have managed to replicate the microscopic, transparent structures that reflect sunlight in such a way as to create the vivid colours of a butterfly wing or iridescent plant.

The discovery has been demonstrated at an exhibition currently running at the worldrenowned Royal Botanical Gardens at Kew, just outside London. What is heartening is that

the exhibition brings together art and science, marrying the works of historic botanical art with the cutting-edge technology of the technique. Lightscaped itself has an Art and Design division.

It is a cliche to those of us involved in it that lighting is an exemplar of the crossroads between art and science. The content of this issue amply demonstrates it, ranging from the knotty, technical complexities of lighting specialist spaces to the exquisite play of shadow and light in Hélène Binet's masterful architectural photography (Viewed in a new light, p12). It brings together the poetry and the prose.

JILL ENTWISTLE JILLENTWISTLE @YAHOO.COM

CURRENT SLL LIGHTING GUIDES SLL Lighting Guide 0: Introduction to Light and Lighting (2017) SLL Lighting Guide 1: The Industrial Environment (2018) SLL Lighting Guide 2: Lighting for Healthcare Premises (2019) SLL Lighting Guide 4: Sports (2006) SLL Lighting Guide 5: Lighting for Education (2011) SLL Lighting Guide 6: The Exterior Environment (2016) SLL Lighting Guide 7: Office Lighting (2015) SLL Lighting Guide 8: Lighting for Museums and Galleries (2015) SLL Lighting Guide 9: Lighting for Communal Residential Buildings (2013) SLL Lighting Guide 10: Daylighting – a guide for designers (2014) SLL Lighting Guide 11: Surface Reflectance and Colour (2001) SLL Lighting Guide 12: Emergency Lighting Design Guide (2015) SLL Lighting Guide 13: Places of Worship (2018) SLL Lighting Guide 14: Control of Electric Lighting (2016) SLL Lighting Guide 15: Transport Buildings (2017) SLL Lighting Guide 16: Lighting for Stairs (2017) SLL Lighting Guide 17: Lighting for Retail Premises (2018) SLL Lighting Guide 18: Lighting for Licensed Premises (2018) SLL Lighting Guide 19: Lighting for Extreme Conditions (2019) SLL Lighting Guide 20: Lighting and Facilities Management (2020) Guide to Limiting Obtrusive Light (2012) Code for Lighting (2012) Commissioning Code L (2018) SLL Lighting Handbook (2018)

sll.org.uk

Secretary’s column/Contents

September/October 2021

Contents

FROM THE SECRETARY

•

•

•

•

•

•

•

•

Anesu A Shumba: Automatic Light Intensity Control System Eby Vincent Mathew: Virtual Light Labs Kate Turley: Biodynamic Lighting to Support Wellbeing in Dementia Maria Englezou: Do we Need to Change the Design of Healthcare Facilities Rooms?

María Teresa Aguilar Carrasco: Lighting Optimisation in 24-hour Work Centres to Promote a Good Circadian Rhythm Mrinalini Kalla: Smart Apartments with Control Systems to Reduce Carbon Dioxide Emission Remedios María López Lovillo: Adaptive Lighting Control System – user-oriented Verity Rose: Drone Lighting – the Impact and the Future

The four finalists will be announced on 25 September with the final of the competition held online in November. The winner of the competition will receive a year's free SLL membership, £1000 and, of course, the SLL Young Lighter trophy.

On 10 September we will have an online presentation from Eleftheria Deko, the multi-award-winning lighting designer who in 2020 lit the Acropolis in Athens. We are very much looking forward to her presentation and we hope you will join us too. We are also looking forward to the [d]arc room pop-up from 22-25 September, including the [d]arc award installations and [d]arc night party. We hope to see you there.

Simon Robinson recently stepped down from the role of chair of the SLL technical and publications committee. During Simon’s time as committee chair he authored LG7: Offices (2015) and LG17: Lighting for Retail Premises (2018). He also authored the SLL Factfile 11: Mechanical Cooling on Lamp Colour and Efficiency. In addition, Simon oversaw the production of many other lighting guides, factfiles and, of course, the SLL Lighting Handbook 2018 by Paul Ruffles. He was

Twitter: @sll100

• For details of SLL Young Lighter

2021: www.cibse.org/society-of-lightand-lighting-sll/sll-events/sllyoung-lighter • For the presentation by Eleftheria Deko on the awardwinning lighting for the Acropolis in Athens: www.cibse.org/society-of-lightand-lighting-sll/sll-events/ upcoming-webinars-andonline-content presented with the SLL Lighting Award in 2018.

Our thanks go to Simon, who we are happy to report will be remaining on the committee.

Following Simon's departure as chair, we are pleased to confirm that Sophie Parry has agreed to take over from him. Sophie joined the committee in 2015, and project managed and contributed to LG14: Control of Electric Light (2016). In 2018, she completed the rewrite of CIBSE Commissioning Code L (Lighting) and was a chapter author and principal contributor to the SLL Lighting Handbook.

In the same year, Sophie was elected to SLL council and was appointed vice‐chair of the SLL technical and publications committee, as well as being awarded a fellowship of the society. In 2020, she was presented with the SLL Lighting Award and completed the new publication LG20: Lighting for Facilities Management. Most recently, Sophie co-authored (with Professor Arnold Wilkins) Factfile 17: Temporal Lighting Artefacts and contributed to CIBSE TM66. In addition, she is a regular speaker on the SLL webinars. It's a pleasure to welcome her in her latest role.

For the SLL Student members who have finished their studies this summer we wish you well in your lighting career. Your SLL Student membership is no longer valid so we would encourage you to now join as an SLL Affiliate member. This will allow you to continue to enjoy the benefits of SLL membership as well as enabling you to progress your career alongside your professional body.

BRENDAN KEELY BKEELY @CIBSE.ORG

2

EDITORIAL

3

SECRETARY'S COLUMN

4

NEWS

5

CONTROLLING INTERESTS Paul Ruffles outlines the first SLL guide on control rooms and the particular demands that lighting these specialist spaces involves

7

SPORTING HIGHLIGHTS Mike Simpson summarises the key changes in the new SLL guide to sports lighting, the first update in 15 years

9

REFLECTED GLORY In a scientific breakthrough the iridescent colours found in nature have been replicated using cutting-edge biomimetic techniques

12

VIEWED IN A NEW LIGHT Light and shadow are powerful creative elements for Hélène Binet. Jill Entwistle previews the forthcoming exhibition of her work at London's Royal Academy

15

THE HUMAN FACTOR Three of the latest LR&T papers focus on the ways that lighting can affect and influence people. Iain Carlile summarises the findings

16

EVENTS

COVER: Le Corbusier's Canons de Lumière, Couvent Sainte-Marie de la Tourette, Eveux, France, 2007, from the Royal Academy exhibition, Light Lines: The Architectural Photographs of Hélène Binet

Courtesy ammann//projects © Hélène Binet

We are delighted to announce that the candidates for the SLL Young Lighter 2021 award have now been shortlisted and as usual they have chosen a fascinating range of topics:

3

News

September/October 2021

THE LATEST NEWS AND STORIES

CALL FOR DAYLIGHT PRIZE CONTENDERS

SLL DOCUMENT ON CIRCULAR ECONOMY WINS PLATINUM AWARD A newly available CIBSE technical memorandum on the circular economy has received a Platinum award, the highest accolade, in the Build Back Better Awards 2021. It also received a Build Back Better Green rating. CIBSE TM66: Creating a Circular Economy in the Lighting Industry, and the Circular Economy Assessment Methods (CEAM-Make and CEAM-Design) were recognised by an independent panel of lighting practitioners and industry figures.

The team which produced the documents was led by SLL immediate past president Bob Bohannon, and project-managed by SLL education committee chair, Kristina Allison.

CIBSE TM66 informs the industry, sector-by-sector, about creating and adopting circular economy principles. It includes a review of current legislation, up-to-date case studies, and FAQs. CEAM-Make and CEAM-Design translate a complex subject into an easy-tounderstand star rating, giving manufacturers and specifiers targeted, usable, independent metrics to compare products and strive for improvement.

'This award is a fantastic affirmation that our work to ensure sustainable futures, looking at the whole life-cycle of lighting and building services and the connection to the management of the earth’s resources, is both very useful and absolutely relevant to our industry,' commented Bohannon. 'The creation of a circular economy is all about design, not just product design, but the design of a whole eco-system of services that keep products delivering value for the longest period of time.'

• Bob Bohannon has just joined the management team of the Lighting Industry Association (LIA) as head of academy and policy. He will coordinate all those supporting policy within the association, creating wider cross-industry links and working closely with the newly created government affairs committee, chaired by Dave Ribbons. www.sll.org.uk / www.buildbackbetterawards.com / www.thelia.org.uk

The WaterLight is an ingenious alternative to solar energy for coastal off-grid communities. A cordless light developed by Colombian renewable energy start-up E-Dina and US marketing agency Wunderman Thompson, it converts salt water – even urine in emergencies –into electricity.

Made of Urapán wood, it needs to be filled with 500ml of seawater to emit up to 45 days of light. One light can provide around 5600 hours of energy, or two to three years of use depending on how often it is needed.

It works through ionisation, a long-established process which sees electrolytes in the saline liquid react

4

with magnesium and copper plates on the interior of the lamp to produce electricity. E-Dina has developed a patented process to sustain the chemical reaction over a prolonged period of time so that it can be used to power a practical light source. www.wundermanthompson.com/work/ waterlight

Nominations for The Daylight Award 2022, a dual biennial prize for research and architecture, are now open.

Previous laureates have included Danish architects Jørn Utzon (the first, in 1980) and Henning Larsen, and US architect Steven Holl.

The 2020 laureates were Finnish architect Juha Leiviskä, UK neuroscientist Prof Russell Foster and US architect, writer and photographer Henry Plummer. Given as a personal prize, it is worth €100,000 to each recipient.

The award was established by the philanthropic foundations Villum Fonden, Velux Fonden and Velux Stiftung, and is conferred in two categories: The Daylight Award for Research and The Daylight Award for Architecture.

The first is given to an individual or a group of researchers whose work puts special emphasis on the effects of daylight on human health, wellbeing and performance.

The architecture award is given to individuals or a group of professionals whose projects and works showcase unique use of and dedication to daylight, particularly those that consider the overall quality of human life, its value to the society and impact on the environment.

The closing date for nominations is 30 September 2021. For more details, go to: www.thedaylightaward.com

WELLBEING KEY THEME FOR SCHOLARSHIP RECIPIENTS The 2020/21 winners of the The Jonathan Speirs Scholarship Fund (JSSF) award are architecture students Laura Carcano and Lawrence Lynch.

Carcano is studying architecture at London Metropolitan University, having gained a first degree from Politecnico of Milano. The award will support her further studies into the role of light in creating responsive, adaptative architecture that improves emotional and physical wellbeing.

A student of the Welsh School of Architecture, University of Cardiff, Lynch is interested in the psychological effects of light. His masters dissertation explored how biophilic aesthetics affect emotional wellbeing. The award will help him continue this research, with the aim of informing his own design work and aiding the general understanding of the emotional effects of lighting within architecture.

sll.org.uk

Guidance

September/October 2021

What mainly characterises the function of a control room is the number and variety of display screens and their various locations and angles to the users

small and simple CCTV control rooms to large process or signalling centres with multiple control desks, consoles and screens. Good lighting is most important in ensuring that the task being carried out is done so safely as well as in comfort.

THE TASKS The purpose of a control room is to clearly present information on the state of a system to the operators. Nowadays there are likely to be a variety of visual display screens, with large wall versions providing information to the whole room, combined with local screens for specific operators. In some process control rooms there may also be consoles, with indicator lights, dials and readout displays. Some process plants and security control rooms also have CCTV screens.

Key considerations are the visibility of gradually changing values on screens and indicators as well as alarm indicators or messages. However, these elements are all the more important when time-critical or safetycritical tasks are carried out. Depending on the type of control room and the equipment being used, different lighting solutions may be required in order to achieve the optimum result.

CONTROLLING INTERESTS The purpose of control rooms, the subject of a new SLL guide, ranges from financial dealing to safety-critical operations such as monitoring nuclear power stations. Lighting them has very particular demands, as Paul Ruffles outlines

Twitter: @sll100

o, what’s difficult about lighting control rooms? Before answering that question, perhaps I had better define what is meant by a control room. What mainly characterises its function is the number and variety of display screens and their various locations and angles to the users.

Some are effectively office spaces and may indeed be part of a larger office building – such as a financial dealing room, a security control room, and some process control suites. Others are larger specialist spaces but are basically a sizeable, open-plan office, such as many railway signalling centres.

Control rooms also vary considerably in size, and the complexity of the tasks that are being carried out. Again, this ranges from relatively

S

SAFETY AND ALERTNESS In all these spaces the operators need to remain alert and, in some situations, to refer to data, safety manuals or instructions presented on paper. Many control rooms operate over 24 hours and the need to maintain the alertness of staff overnight is important – especially when they are dealing with safety-critical operations such as monitoring and control of nuclear power stations, or large petrochemical or processing complexes. For these reasons there normally needs to be a fixed background level of light throughout the space that provides a bright and stimulating environment to maintain alertness. This can be supplemented with local task lighting for operators who need to refer to written or diagrammatic information on paper at their workstation.

The new LG22 overlaps in some of its recommendations and refers to supporting information in several other relevant SLL lighting guides – LG7: Office Lighting; LG1: The Industrial Environment, or LG19: Lighting for Extreme Conditions, for instance.

Lighting within a control room contributes to the comfort and efficiency of the people working within it. Lighting levels can affect people’s moods, concentration levels and

E

5

Guidance

September/October 2021

Top of display within upper limit of acceptable viewing zone for fifth percentile female operator seated in relaxed posture Bottom of display visible over top of workstation displays to fifth percentile female operator seated in relaxed posture

Not to scale

Fig 1: the range of screen adjustment might be limited to avoid complex changes between the various users from one shift at that workstation to another

E

perception of comfort, often without them realising. Lighting also has a physiological effect on us by affecting our serotonin levels.

The following sections provide guidance on approaches to optimising the design of control rooms with all of this in mind.

CONTRAST, SIZE, VISUAL ACUITY, SIGHT LINES The workstation worksurface forms one of the primary parts of the visual field for its users.

It is vital that its visual properties minimise high contrasts in luminance between all display screens at the workstation and with all printed materials that may be used on the workstation surface. Minimising high contrasts also reduces the possibility of providing reflected glare, further reducing the potential for visual discomfort to the users.

Not to scale

Fig 2: viewing angles and distances to local and remote screens vary

Each display screen at a workstation is typically mounted on either a bracket, rails or stands that may allow the users to achieve a range of adjustability. This might include: •

• •

Adjusting the distance between each individual display screen and the front of the workstation Adjusting each screen’s angle, tilt and swivel Allowing the screen to be adjusted in height to allow for different user eye heights

But in many workstations the range of modification is limited to avoid complex adjustments between the various users from one shift at that workstation to another. Thus, adjustments are often a compromise.

OVERVIEW WALLMOUNTED SCREENS/DISPLAYS

'The need to maintain the alertness of staff overnight is important – especially when dealing with safety-critical operations' 6

Screen displays on walls are normally large and fixed in location such that the information on them can be clearly read or interpreted by groups of users in the room. The lighting in the room needs to be selected and located such that no disabling reflections appear on the screen when it is viewed from any of the locations that a user may need to view it from.

ADVANTAGES OF MOCK-UPS Because of the complexity of the set-up of lighting and screens in relation to the desks there is often an allowance in time and money within the design process to create a mock-up of one or more desks and related screens. These mock-ups are often also being used for additional purposes: to trial furniture, screen types and even the way that software is

displaying information on the screens.

Certainly, where local task lighting is being considered the trials of various ondesk and off-desk solutions can be very useful – especially where the actual future operators of the space are involved in the evaluation. Such trials with local task lighting will ensure the selected luminaires cannot be accidentally adjusted to throw glaring light at the user, their neighbours or on to any part of the screen where disabling reflections may degrade or obscure important information.

This helps both inform the design process and get user acceptance of the task lighting in advance.

SUGGESTED LIGHTING TECHNIQUES The guide has a large chapter describing many ways to provide the right lighting in control rooms. The acceptability of each is often determined by the rooms and task characteristics. High rooms, for instance, allow uplighting and direct/indirect lighting schemes to be considered.

Another chapter looks at the advantages and disadvantages of allowing daylight into the room. Most people prefer to work in a daylit space and windows provide a valuable visual contact with the exterior, even when a workstation is far from the window. However, there is potential direct glare from the sun and reflected glare on display screens of bright clouds and the sun. Blinds or some other sun-screening device are normally needed to mitigate or prevent this.

The control of the lighting is also covered as there is a need to maintain a good basic level of lighting across the control room, while allowing some local variations or user adjustment where this assists with the user's work and does not compromise colleagues.

Finally, the guide covers the vital area of emergency lighting and standby lighting. While even minor security control rooms and the like need emergency lighting for the safety of the staff in the event of a power failure, more major control rooms need to operate normally and so standby generators and UPS systems are provided to run all or part of the lighting during a power failure.

Lighting Guide 22 (LG22): Control Rooms is scheduled to be published towards the end of the year. Paul Ruffles is the sole author

sll.org.uk

Guidance

September/October 2021

SPORTING HIGHLIGHTS

p Corinthians Stadium, São Paulo, Brazil, the opening venue for the 2014 World Cup

Against a background of major developments in technology, Mike Simpson summarises the key changes in the new SLL guide to sports lighting, which is getting its first update in 15 years

ighting Guide 4 is one of the latest SLL guides to undergo a review by a panel of experts to bring it up to date. So what is new? It is worth going back a few years to see how it has changed over the past three decades.

L

Twitter: @sll100

In 1990 it was published to reflect the current state of lighting, and particular attention was given to reflecting the input from the many governing bodies for all the sports mentioned. Some had very specific requirements, usually drawn from what was considered best practice, while others had no recommendations at all.

The next edition appeared in 2006. The intervening years had seen the publication of CEN BSEN12193, which harmonised lighting practice over Europe, though the influence of CEN standards has a wider geographical reach. In this standard, sports were grouped according to the difficulty of the task (for example, speed of ball, size of ball, viewing distance) and the level at which the sport was played (recreational, club, elite and so on).

Generally at higher levels things move faster, although a hockey ball at recreational level can move just as fast as at club standard. So the 2006 edition of LG4 was broadly rearranged to follow the CEN format.

It's worth pointing out that while the CEN standard is a series of lighting criteria, LG4

contains additional practical guidance based on the experience of those who have had to design and plan installations.

Following on from the 2012 London Olympics, significant changes to the requirements for broadcasters were implemented in many standards including both CEN and LG4, as it was realised that broadcast technology was moving faster than lighting guidelines. At the same time we were beginning to move into the age of the LED. We have also seen a greater emphasis on environmental issues in terms of energy and obtrusive light.

It is these factors that have influenced the changes to the latest version of LG4.

The new guide will reflect the fact that any new installation will in practice be based on LED technology and any refurbished installation will do the same. LEDs offer energy savings and will generally maintain their performance for a longer time than traditional light sources. The LxBy definition gives a clear indication of depreciation throughout life which is now a luminaire characteristic rather than one of the light source. One thing that is

7

E

Guidance

September/October 2021

Aerial view of a tennis club with light controlled at the boundary

E

often missed is the influence of temperature, and measuring an outside floodlighting installation in the winter will give higher results than in the summer. The move to an LED-only standard mainly affected the chapters that dealt with the technology.

It was quite strange

'The most significant changes over the past 10 years have been the requirements for broadcasting' eliminating the references to traditional lamps that have been a stable part of lighting guides for decades, but in reality they served no practical use in a guide for the 2020s.

One thing that didn’t change was the lighting levels. These were reviewed and considered to be sufficient for the participants and as far as possible are

8

aligned to the recommendations of governing bodies. One sport that was taken out was greyhound racing which was always an odd fit in a guide for sport.

The most significant changes over the past 10 years have been the requirements for broadcasting. Lighting for sports broadcasting has always been one of the main considerations for any larger venue and with live events cancelled to spectators for the past year it has only brought more sharply into focus the need for high-quality pictures to replace the live experience.

TV cameras, in line with many electronic technologies, improve in performance every few months. This means you can do more with less. While in the past there were specialist cameras for super slow motion pictures, now that is available as a standard feature. So while before you would only have to focus on these for certain camera locations, now you have to assume every camera will be taking slow motion pictures.

Cameras are becoming smaller and lighter so handheld ones can do more than they did in the past. This means that television producers will include more close-up shots to make the broadcast more interesting and enticing for the viewer compared with a few cameras covering the whole field.

For the 2012 Olympics, broadcast was mainly high definition with some events shown in 4K. For Tokyo 2020 it was 4K as standard with some 8K. This doesn’t mean lighting levels have to be higher but it does mean a greater consistency is required over the field of play. So colour tolerances have to be smaller and uniformities have to be

higher. We have seen the introduction of the uniformity gradient to control changes in lighting level over the field of play.

UGR (unified glare rating) is used as a measure to control glare for indoor venues and glare rating for outdoor areas, although the familiar GR is now replaced by RG in line with international practice. However there are venues which are too large for the application of UGR and too small for the traditional use of RG . This was also being addressed within CEN, and by going back to the original authors of the glare rating and looking at recent research, RG is now applied where heights are more than 10m. This gives a practical glare rating for larger indoor venues such as arenas.

Recommendations for colour rendering have been rationalised in line with LED technology.

So we now recommend a colour rendering of ≥70 for outdoors and ≥ 80 for indoors independent of class.

From a designer's point of view one of the significant changes over the past few years will have been the growing requirement to submit obtrusive light calculations for exterior projects. This is not just a quantification of light going upwards into the sky but also on to adjacent properties. Here we fully adopt the requirements set out in CIE150: Guide on the Limitation of the Effects of Obtrusive Light from Outdoor Lighting Installations.

In drafting the latest version of LG4 we have made the changes that were required to bring it up to date in terms of current practice and technology. It will also be in line with the latest publication of BSEN12193 which was published in 2019. It has also been informed by developments in other sports lighting guides to achieve as much harmonisation as possible.

Sport is very much a global application where standards are applied across geographic boundaries. LG4 is forward-looking to ensure that it will remain relevant to the changing world of sports lighting.

Lighting Guide 4 (LG4): Sports is scheduled for publication towards the end of the year

LG4 task group: Mike Simpson (chair), Giulio Antonutto, Russel Evans, Richard Morris, Dr Alan Smith, Kevin Theobald

sll.org.uk

Light and colour

© Roger Wooldridge

September/October 2021

REFLECTED GLORY In a scientific breakthrough the iridescent colours found in nature have been replicated using cutting-edge biomimetic techniques – and this year can be seen for the first time at Kew Gardens Twitter: @sll100

ver since Newton fragmented a beam of light into a rainbow we have been aware of the complex relationship between light and colour. As the artist Turner is quoted as saying under his depiction on a £20 note, 'Light is... colour.'

But while the basic colours of the rainbow seem a simple proposition, it

E

9

E

Light and colour

© Roger Wooldridge

September/October 2021

Composition of Sunlight by Andrew Parker (also previous page)

has become increasingly clear just how complex colour can be. We have come to understand that what we may see as one shade is perceived in totally different ways by other animals, including their ability to see ultraviolet wavelengths. We have also become aware that while we can reproduce many hues through mixing pigments or combining LEDs in different permutations – 16 million is the usual estimate – certain

'Pure Structural Colour involves cutting-edge technology and takes inspiration from the natural world to synthetically produce any shade of colour in its most vivid form' 10

colours found in the natural word have eluded us. Until now.

An exhibition, Naturally Brilliant Colour, running at Kew Gardens until the end of September, reveals the brightest colours ever to have been created, known as Pure Structural Colour. It involves cutting-edge technology developed by scientific researchers at Lifescaped lab and takes inspiration from the natural world to synthetically produce any shade of colour in its most vivid form. It is an example of bioinspiration – replicating structures found in the natural world for the benefit of human design. In nature, microscopic structures within the surface layers of plants and animals reflect sunlight in a specific way to generate bright colours – the blue-green tinges of iridescent plants, and the wings of tropical butterflies and hummingbirds.

Lifescaped has found a way to reproduce this natural phenomenon for the first time using only transparent materials. As it involves microstructures rather than pigments, the colour also never fades. The application for art and design is clear but according to Lifescaped, Pure Structural Colour also has the potential in wider industry to

replace pigments that may not be sourced ethically or sustainably.

Lifescaped director Prof Andrew Parker has been exploring this field since the 1990s when he spent much of his time underwater and noticed the extraordinary diversity and brightness of marine colours. At the Australian Museum and Macquarie University he discovered new types of ‘structural’ colours, generated by microscopic structures in transparent materials, rather than pigments or dyes.

In 1998, he published the Light Switch Hypothesis. He discovered that the evolution of image-forming eyes, and vision in the general community of animals, triggered the 'Cambrian explosion' – the Big Bang of evolution.

As a result of this, the US Secretary for Defense instigated work on The Cambrian Programme – biomimetic predictive software that emulated events in nature. This grew to include 'ant colony optimisation', a probability technique for solving computer problems. Based on this work, The Royal Institution selected Parker as one of the eight Scientists for the New Century.

From 1999 to 2006, he formed a biomimetics group at Oxford University.

He is currently a visiting senior research fellow at Green Templeton College, University of Oxford, where he heads a research team on photonic structures and eyes: evolution, development and biomimetics.

Parker is also an artist who has used Pure Structural Colour in his artworks (as well as being a scientific research lab, Lifescaped has an Art and Design Studio).

Some feature in the exhibition at Kew which marries the art and science of light and colour. The display brings together works by influential botanical artists such as Robert John Thornton (1768-1837) and contemporary artist Julia Trickey, and details various artistic techniques which have been used to depict the brightest and most vivid colours found in nature, as well as the use of structural colour.

Other works demonstrating the technology include a large-scale kaleidoscope containing glass elements coloured with Pure Structural Colour: the brightest flashes in the ever-changing

sll.org.uk

Light and colour

© Roger Wooldridge

September/October 2021

As iridescence involves microstructures rather than pigments, the colour never fades

Examples of Pure Structural Colour

Twitter: @sll100

© Roger Wooldridge

projected image convey how some plants and animals use natural structural colour to make themselves visible in dark forest undergrowth.

Also on display are prototype accessories coated with structural colour to give visitors a taste of its potential in the world of fashion and design. 'Pure Structural Colour is the most vivid colour I have seen, reminiscent of the jewel-like shades that until now could only occur in nature,' says award-winning designer Marc Newson. 'This is what makes it so exciting, bringing something usually glimpsed on a small scale, like the hues found in hummingbirds, tropical fish and beetles for example, into a world of huge possibility. It is very versatile in scale, with applications ranging from large surfaces to tiny flakes.'

Naturally Brilliant Colour runs until 26 September 2021 at the Shirley Sherwood Gallery of Botanical Art, Royal Botanic Gardens, Kew, Richmond, Surrey, UK • www.kew.org/kew-gardens/whats-on/naturallybrilliant-colour-exhibition • https://lifescaped.com

11

Exhibition preview

September/October 2021

VIEWED IN A NEW LIGHT

Courtesy ammann//projects © Hélène Binet

Light and shadow are powerful creative elements for Hélène Binet, known as 'the architect's photographer'. Jill Entwistle previews the forthcoming exhibition of her work at London's Royal Academy

Vitra Firestation, Weil am Rhein, Germany, 1993, by Zaha Hadid Architects.

Digital black-and-white silver-gelatin print, 80 x 80cm

ight, says Hélène Binet, 'will give you the best melody'. A building will vary according to the light of its location, the season or time of day, and will have an optimum moment that she seeks to capture with her camera.

L

12

If possible, she will study the site beforehand to understand its underlying conditions and the intention of the architect, determining exactly the right moment to record it.

'The best thing is to spend time looking at a building,' she said in an interview with Lighting

magazine. 'Of course I can't always control the weather – sometimes I think I really want to do this with cloud and then we have sun, or the opposite. The more time I have to spend and understand the light of the place, the more successful will be the shot.'

sll.org.uk

Exhibition preview

Courtesy ammann//projects © Hélène Binet

September/October 2021

Lingering Garden, Suzhou Gardens, China, 2018.

Digital C-type print, 80 x 80cm.

London-based, Swiss-French architectural photographer Hélène Binet has built a formidable reputation over the past 30 years and has forged long-term relationshsips with some of the leading architects of the age, notably Zaha Hadid, Daniel Libeskind and Peter Zumthor. The forthcoming exhibition, Light Lines: The Architectural Photographs of Hélène Binet, will span her career, showcasing around 90 images of more than 20 projects by 12 architects.

One of her virtues is making the complex simple, often focusing on a fragment of a building rather than attempting to portray the whole. She mainly takes black-and-white images that encapsulate light, space and form. Her juxtaposition and exploitation of light and shadow is why she insists on a film

Twitter: @sll100

rather than digital camera, and why her work is predominantly monochromatic. 'You get a different quality of light and shadow, film is more sensitive, film is more spontaneous,' explains Binet. 'Black and white will tell you more about how something reacts to light.

We cannot see a building or a material without light, we are not able to understand the quality of it without light. We put an object inside a beam of light and then we understand it.

It's very complex.'

Binet was born in 1959 in Sorengo, Switzerland, and studied photography at the Istituto Europeo di Design in Rome, where she grew up. After completing her studies Binet worked as a photographer at the Grand Théâtre de Genève opera house, where she photographed various theatrical performances

for two years. She came to live in London in the 1980s when her husband, architect Raoul Bunschote, founder of Chora, was teaching at the Architecture Association. She met Alvin Boyarsky, director of the AA, who gave her an opportunity to photograph her first architecture book and set her on her career path, also encouraged by architects Daniel Libeskind and John Hejduk.

Binet's work has been published in a wide range of books (including a Phaidon monograph, Composing Space, published in 2012) and shown in both national and international exhibitions, including in the permanent collection of MoMA, New York.

She was made an honorary fellow of RIBA in 2007, and in 2015 was awarded the Julius Shulman Institute Excellence in Photography

13

Exhibition preview

Courtesy ammann//projects © Hélène Binet

September/October 2021

Courtesy ammann//projects © Hélène Binet

Parish Church of St Matthäus, Düsseldorf, Germany, 2020, by Gottfried Böhm.

Digital C-type print, 102 x 80cm

MAXXI Museo Nazionale delle Arti del XXI Secolo, Rome, Italy, 2009, by Zaha Hadid Architects.

Digital black-and-white silver-gelatin print, 80 x 102cm

14

Award. She is one of the Royal Photographic Society’s Hundred Heroines.

The RA exhibition will be organised in themes that are echoed throughout Binet’s career, exploring connections between ideas, places and landscape. It will begin with one of Binet’s most iconic images, a large square format print of Zaha Hadid’s Vitra Fire Station, completed in 1993 and photographed soon after.

Other works will include shadows and spaces at Le Corbusier’s La Tourette monastery in France and the Jantar Mantar Observatory in Jaipur, India, where Binet exploits the high contrast of the site's light and shadow.

The next section returns to Binet’s longstanding professional relationship with Hadid. Black-andwhite images of her best-known works will include the MAXXI Museum of Art in Rome, the Glasgow Riverside Museum of Transport and the Rosenthal Center for Contemporary Art in Cincinnati. These images will be hung alongside photographs of works by less well-known architects.

The final section 'will show powerful and simple images of Binet’s observations of the essential elements of architecture: walls that catch shadows and act as a foil for nature, and ground planes that show the use of architecture across time'. These include Binet’s famous images of the Thermal Baths at Vals by the Swiss architect Peter Zumthor, hung alongside landscaping and pathways at the Acropolis designed by Dimitris Pikionis in the 1950s. Her recent work includes a set of Five Churches in Cologne by Gottfried Böhm, commissioned to celebrate the architect’s centenary, and an iconic yet rarely seen private house, Can Lis,

by Jørn Utzon.

The majority of the buildings represented date from the 20th and 21st centuries, but there will be three projects from earlier periods: as well as the 18thcentury Jantar Mantar Observatory, there are 18th-century churches in London by Nicholas Hawksmoor, and the Lingering Garden of Suzhou, China, parts of which date back to the 16th century.

She has observed that architects have different attitudes to light according to their provenance and culture. 'In Nordic places where light is so precious, architects spend a lot of time thinking about this light and how to use it in a building,' said Binet in her Lighting interview. 'I love the work of Zaha but the light was not important to her. She grew up with all the light she wanted, and the building is not about collecting light.

'Even where there's a tiny bit of daylight coming in, it makes a different moment, a different mood, it's so precious,' she adds.

Light Lines: The Architectural Photographs of Hélène Binet can be seen at the Jillian and Arthur M Sackler Wing of Galleries at the Royal Academy, London, from 23 October 2021 – 23 January 2022

sll.org.uk

LR&T essentials

September/October 2021

THE HUMAN FACTOR Three of the most recently published Lighting Research and Technology papers focus on the ways that aspects of lighting can affect and influence people.

Iain Carlile summarises their findings xamining how colour rendition influences a person's perception of the architectural environment, Royer et al’s paper explores best practice for conducting psychophysical experiments. The authors note that while there has been a proliferation of research in this field over the past decade, a lack of methodological rigour can make the interpretation and application of results difficult.

The authors identify a range of issues in published results on colour preference, colour naturalness and other subjective aspects of colour rendition, and make recommendations on how research can be focused not only to resolve pressing questions in this field, but also to inspire new research. The recommendations include:

E

• Clearly expressed research questions and explicit hypotheses that build on the existing body of knowledge • Spectral power distribution and visual target stimuli engineered to investigate the research questions • Experimental design to lessen potential biases • Thorough reporting of experimental conditions and statistical analyses • Results that are contextual, avoiding overgeneralisation The authors hope that this paper will encourage high-quality credible research that speeds scientific progress and best uses the resources available.

Ryan et al investigate the use of lighting to

Twitter: @sll100

p Chasing LED lighting used on a railway platform staircase to encourage bi-directional movement of passengers (Ryan et al)

influence passenger behaviour at train stations, presenting a study of two different lighting interventions: • The use of projected light on to the platform to identify preferred waiting locations • Chasing LED lighting on a staircase to encourage bi-directional movement For operational safety reasons, the field study was conducted at a small train station in the south-west of England on the London mainline.

Both applications were controlled using IoT (Internet of Things) technology integrated with the operational railway systems. From the results of the study the authors conclude that the lighting interventions were successful in being noticed by and initiating responses in passengers, which should encourage further studies in this area.

Also considering the application of lighting, Lo and Steemers have studied different real-world lighting scenarios, evaluating the overall impression of concert lighting at King’s College Chapel in Cambridge, UK. The study concerned the different roles of the people present (audience, conductor and musicians), the relationships between subjective attributes and the objective measures of light.

From their analysis of the 624 respondents, Lo and Steemers found no statistically significant subjective-objective relationship

for visual balance, appropriateness of lighting, comfort and overall impression.

However, using the subjective attributes as predictors produced rather more significant results. These suggested that the perceptual process was bi-level with higher level perceived qualities (visual balance, appropriateness/comfort and overall impression) accounted for not by objective measures but by lower level subjective attributes (visual clarity, brightness, visual uniformity and spatial intimacy).

The authors note that their analytical approach could be used to evaluate other realworld complex lit environments, but is likely to pose a technical challenge in informing lighting design prior to construction.

Iain Carlile FSLL is a past president of the SLL and a senior associate at dpa lighting consultants Lighting Research and Technology: OnlineFirst In advance of being published in the print version of Lighting Research and Technology (LR&T), all papers accepted for publishing are available online. SLL members can gain access to these papers via the SLL website (www.sll.org.uk) Recommended methods for conducting human factors experiments on the subjective evaluation of colour rendition M Royer, K Houser, D Durmus, T Esposito and M Wei Field testing two innovative lighting interventions to influence waiting behaviours and movements on stairways in train stations B Ryan, M Hallewell, N Hughes, N Coad, J Eliseu, M Lira, A Grant, N Parrott and K Thompson Evaluating the overall impression of concert lighting: An integrated approach VWL Lo and KA Steemers

15

Events 2021

For details of all upcoming webinars, go to: www.cibse.org/society-oflight-and-lighting-sll/sll-events/upcoming-webinars-and-online-content For previously recorded CPD webinars (including regional webinars), go to: www.cibse.org/society-of-light-and-lighting-sll/sll-events/pastpresentations

EVENT [D]ARC ROOM POP-UP@DESIGN LONDON Magazine London, Greenwich Peninsula Date: 22-25 September 2021 www.darcroom.com

ONLINE EVENT SHAPING LIGHT FOR HEALTH AND WELLBEING IN CITIES (International Conference organised by the ENLIGHTENme Consortium, an EU project) Date: 16-17 December 2021 www.enlightenme-project-conference.com

AVAILABLE WEBINARS INCLUDE BATS: WHY DARK SKIES MATTER (SLL and CIBSE Home Counties North West) Looking at bats as a species and also examining relevant legislation.

Speakers: Keith Cohen, consultant ecologist; Andrew Bissell, FSLL, director of lighting design, Cundall, and SLL president-elect MIKKI KUNTTU: FINNISH LIGHTING AND SET DESIGNER (SLL and CIBSE North West) Kunttu, lighting designer, set designer and screen content designer for theatre, live entertainment, television and visual arts, talks about his creative process, outlining a case study of his production design for Swan Lake at the Royal Danish Ballet in 2015.

DELIVERING THE CIRCULAR ECONOMY FOR THE LIGHTING INDUSTRY (SLL and CIBSE Home Counties South West) Chair: Hakeem Makanju, CIBSE HCSW regional chair, and David Mooney, SLL representative for HCSW Speakers: Bob Bohannon, FSLL, SLL immediate past president; Kristina Allison, CEng MCIBSE MSLL, chair of the SLL education and membership committee; Roger Sexton, FSLL, business development for Stoane Lighting; Tim Bowes, MSLL, head of lighting application for Whitecroft Lighting

16