The vast Planet of Visions exhibit - the largest at the Expo - suffered a setback shortly after the Expo opened, when the original smoke effects contractor was removed from the project. In a major dilemma, someone at this point remembered that Hanover was home to a smoke effects specialist - The Smoke Factory.
The Smoke Factory’s Florian von Hofen told us: "This was probably the most complex smoke effects project ever undertaken - not the biggest, but the most complex. It is a vast exhibit, visited by 30,000 people each day. The budgets would not allow for permanent technical personnel, so everything had to be automated."
By the time The Smoke Factory was called in, the set had been built, and there was no opportunity to pre-plan for anything. "We had to live with every limitation that had already been built in to the exhibit," says von Hofen. What he and his team came up with was certainly complex: the system required 42 smoke machines covering the 16 separate scenes of the display, all of which are controlled via an Avenger Show Controller. The entire exhibit runs through a day/night loop lasting five minutes, at which point the loop returned to point zero - meaning all smoke had to have gone. In addition to this, Hall 9’s highly sophisticated ‘sniffing’ smoke alarm system had to be taken ito consideration. This analyses regular samples of the air in the hall, looking for significant changes that could indicate a fire.
Faced with achieving a wide range of effects, including steam jets, mist, clouds and ground fog, von Hofen took the unusual step of choosing to stick solely with glycol-based fluids, confident that he could achieve the necessary effects with that alone. He says: "Smoke from Glycol-based fluids usually comes out - and goes up. However, in this very controlled environment, I was able to achieve the wide range of effects required very satisfactorily." He’s not saying how, of course.
Von Hofen made use of a webcam to monitor the effects: from his desktop he could clearly see how the system was working. Amazingly, for such a complex system, it requires just one hour of maintenance per day, and this is almost entirely for fluid replacement, says von Hofen: "If we had been involved in the project earlier, we could have made allowances for larger fluid containers within the set, but this was not possible, so we have to refill more regularly."