Smoke
For chimney fires, the SFX team uses a false chimney and makes sure it doesn’t leak into the building. In combination with a ZR12 machine, a sturdy grey box that delivers smoke through a wide nozzle, they use an oily solution to make the smoke, which is safe to breathe and won’t do damage to plants or animals. The machine is in the chimney, so the SFX team can control it with a remote, and because the smoke has to stay the same consistency throughout the day, the team can turn it up or down depending on external elements like wind.
For atmospheric smoke, the SFX team can cover an entire forest with their set-up. The team lays down flat tubes that are normally used for irrigation, but Jonathon Barras and the team fill them with air. They are up to 100 meters long, surround a whole filming area and, if needed, can be joined together to become 200 meters long. They can be fed from one end, both ends, or the middle, depending on what coverage is required. Large gas burners are brought in to heat the pipes and create the smoke.
Snow Candles
Snow Business provides all the snow candles for the show. What is a snow candle? A certain type of paper is soaked in a chemical that makes it burn slowly, and as it does, the candle creates a very fine ash that the SFX team spins in galvanized buckets. If they find the right wind, it drifts nicely through shot; if the wind is not moving in their favor, you get crew members’ faces full of fake snow and a lot of complaints. According to Barras, snow is one of his favourite things to do, but also one of the hardest natural phenomena to recreate. “I took fake snow to Iceland,” he told me, “but we never had to use it.”
Pyrotechnics
The SFX team has only used a few pyrotechnics on Season 3 – swords hitting each other, swords striking rocks. Pyrotechnics, according to Barras, is every boy’s dream. You get to blow things up and never have to put them together again. The SFX team is pretty excited whenever the pyromancer appears on the show, as it suggests that the team might get to blow some more stuff up. Safety-wise, it is probably the strictest of all elements – you can’t have mobile phones on set or use radios, which can be limiting, especially for the ADs who have to talk to each other constantly.
Rain effects
For rain, the SFX team uses the same type of pumps the fire department has on its trucks. If possible, they connect to hydrants or pull from rivers, if we are close enough. If we aren’t, they have huge 20,000-liter dams to hold water. For big rain (like with Arya in Harrenhall’s courtyard, or over the battle in the Blackwater scenes) they uses a spinner on a crane about 100 feet in the air. The water pressure spins the head in a huge circle of rain, maybe 30 meters across, and they put four of those on the crane at once.
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