The annual Sydney light festival is back bigger and brighter than ever. But what many people don’t realise is the incredible light installations are a mix of engineering meets art.
Since its launch in 2009, Vivid Sydney has upped the ante on digital creativity and showed how science and art can combine to delight millions.
Michael Hassett, founder and managing director of technology provider TDC has been working alongside Vivid Sydney artists for 12 years. He told create that the process of bringing images to life is usually the other way around to what people might expect.
“The artists will be given a building and TDC will give them the specifications for their design,” he said. “We tell them that the canvas is say 8000 pixels wide and 4000 pixels high, and we need you to create the file, typically in HAP+ Codec. Then they create the content on a 3D CAD format within the specifications we’ve given them.”
This year, TDC is working on 27 sites across Sydney, including teaming up with creative studio Spinifex and Ken Done for From Sydney With Love on the façade of iconic Customs House. With ornate balconies, it’s not the easiest building to project on to — but it’s nowhere near as complex as the famous sails of the Sydney Opera House.
“We’re usually running 16 channels of very high resolution output in order to put the signature on the building,” Hassett said.
“One of our key challenges is that rarely are we able to put the projectors in optimal positions. For the Opera House, we are usually about 575 metres away from the building, with an alternative position that is 1000 metres back. Thankfully, ships are not allowed in the harbour after sunset during Vivid which makes life a little easier.”
Hassett said that while they usually divide a building into 30 or 40 segments to adjust for fine detail, some artists are working down to individual tiles or rivets.
“When you’re projecting hundreds of metres away, one millimetre of variance at our end can be 50 millimetres of variance on the building,” he said.
“We use a number of techniques, including simple binoculars and very long lens television cameras with large monitors so that the engineers are focused in on a couple of bricks or the corner of a window, and they’re adjusting the image to sit perfectly within that object.”
The pixels the engineers are projecting might only be a couple of microns on the computer screen, but on a building they are millimetres wide. On a structure such as the Opera House, depth between the front surface and the upper rear surfaces can give up to 30 metres of variance.
“We usually have multiple projectors overlapping each other in the one area. Typically we are using angles that could be 45 degrees off axis horizontally and vertically,” Hassett said.
“The skill of the engineer really shines when they have to manipulate pieces of hardware in order to shape the image to the building, so that when we project a circle it’s round or a rectangle is square — and this is all effectively being done in real time.”
Preparation for Vivid usually begins around six-to-eight weeks from opening night, with projector alignment and colour testing often taking days of work for each building.
Engineering meets art meets safety
Engineers Australia member and structural engineer Alexandra Hunt MIEAust, leads the Vivid team at Event Engineering. She told create that the role of engineers is to maintain public safety while preserving artistic vision.
“Our main aim is to ensure that the installations are able to withstand a reasonable level of human interaction, such as accidental knocks and children grabbing things,” she said.
Hunt said that she uses guidance from Standards Australia alongside engineering skills to establish appropriate design wind speeds for the structures.
“These parameters enable us to develop an achievable wind management plan which the event crew can implement,” she said. “We cannot design structures to withstand the same wind speeds as permanent structures without significantly impacting the artistic intent. At the same time, it is not practical to expect that all of the structures could be de-rigged or dismantled for an approaching storm.”
In terms of analysis, Hunt said that a lot of the installations involve materials and forms which cannot realistically be entirely modelled and analysed with traditional methods.
“When engineering art there is no black and white answer,” she said. “If the analysis results seem too good to be true, then you have to trust your judgement and increase the safety margin or strengthen any weak points on the critical path.
“If there is material or a product being used in an unusual, non-standard way the best approach is to go to the workshop or take a prototype to site to get a feel for how it behaves.
“This is especially relevant when we are looking at robustness and serviceability.”
All structures being installed outdoors for Vivid require design and inspection engineering certificates.