A Month Shooting Effects Shots for Nat Geo and Sky in Slow-Mo 3D. Part 1 of 3.

The "coffin" set used to simulate a collapsed building.

Since the beginning of March I have been working as 3D supervisor and sterographer for a 3D shoot for Nat Geo and Sky. Working with DoP David Barlow (renowned for his miniature and In-the-womb work) we were the effects unit for a big budget series of 4 programmes with the working title of “Storm City”. The programmes are hosted by Ben Fogle and explore some of Natures most extreme disasters including Hurricane, Tornadoes, Earthquakes and Tsunami’s. With a budget in the millions this is high end stuff. Our job was to provide material to illustrate many of the interviews with disaster victims, often reconstructions of the situations the people found themselves in. As most of this was to be shot in 3D slow motion, we were using a pair of Red Epics on a Hurricane Rig 3D rig owned by David. Our first reconstruction was of a collapsed building with people buried under the rubble, our “studio” was an industrial unit in Southampton. The set builders had constructed a small set filled with rubble and collapsed concrete. The surprise for me when I walked on to the set in the morning was just how small it was. The  whole set was built in a box measuring about 10ft by 6ft and just 4ft tall, it became know as the “coffin”. The idea was that by using such a small set we could create the impression of the trapped people being in a very confined and claustrophobic space. The illusion worked very well and as the set was contained within a box type enclosure we could shoot into the coffin from 3 sides for a wide variety of shots. All the debris, concrete and rubble was made out of light weight materials, yet looked totally convincing.

The coffin and the 3D rig.

To help tell the story of the people trapped in the collapsed building we used a lot of slow motion with dripping water and falling dust to accentuate the sensation of time passing slowly. Shooting at 200fps we did encounter issues from strobing lights from time to time. This is one of the real slow mo nightmares as the strobing is rarely visible to the naked eye and it’s only when you play the clips back that you see the issue. Some of the problems were down to running the HMI’s off different mains phases, others were problems with the bulbs and the arc rotating around the electrode. In order to get enough light for the higher frame rates we often used a pair of 4K HMI’s with fill from 1.2K HMI’s.

The collapsed building scenes were finished off with shots of wires arcing and sparking. This was achieved through the use of small pyrotechnic charges that contained magnesium as this gives a brilliant white flash much like a spark.

DoP David Barlow checking focus for debris the tornado shoot

Our next scene was a reconstruction of a child getting sucked out of a bedroom window by a Tornado. For this we had a 3 wall bedroom set with a window. To simulate the effects of the tornado we had a wind machine made out of a hovercraft fan. This was then complimented by smaller fans to fill in any gaps and add extra circulation and turbulence to the wind storm. The last piece in the equation was an air canon to blast out the window with a shockwave of air and debris. This was one of the messiest shoots I have ever been involved in. We used fullers earth, leaves, twigs and insulation material to fill the air with blowing debris as well as a smoke machine and a hazer machine. This was the first time I’ve ever had to wear overalls on a set, but it was not going to be the last! Once that hovercraft fan got going it really was like being in a tornado. Anything not bolted down would fly around and the dirt and debris went everywhere. It was great fun, but after every take the 3D rig, lenses and cameras would need a strip down and clean. Sadly I have been asked not to show pictures of the sets until the show airs later in the year. I wish I could as it’s quite amazing to see how we recreated these scenes in what was a fairly small space.

Thundervoltz lightning machine.

As I always had a great view of what was being shot on my 3D monitors I also had the job of operating the lightning machine. This machine used a giant 70,000 watt strobe lamp to create massive flashes of light to simulate lightning. It made quite a loud zap every time I pressed the button, lots of fun but I had to be careful not to overdo it as if the flash duration was too short we could get flash band issues due to the use of CMOS sensors.  Our next scene was of the tornado aftermath. We had to recreate a night time scene of total destruction, giving the impression of destroyed houses and scattered belongings. It’s amazing what a good art department can do when assisted by copious amounts of smoke and haze from the hazer along with some subtle lighting effects. Our next scene took us from tornado alley in the USA to the UK for a reconstruction of a tree falling through the roof of a house. I’ll tell you how we did that and recreated an earthquake in the next instalment. In the final instalment I’ll tell you about how we recreate falling electricity cables, and ice storm and bury a house in an avalanche!

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