Case Study

Avengers 2: The Age of Ultron

“I take timecode very seriously, seeing it as part of the camera. Although it doesn’t really affect us on set, later down the line, a break in timecode can cause other areas a whole world of problems.”

Peter Welch, digital imaging technician (DIT)

Syncing feature film action sequences

Fast-paced chases, sprawling locations, high-speed crashes and exploding massive amounts of pyrotechnics – feature film action sequences are full of unpredictability. They are also incredibly costly to get wrong. So when preparing for these pivotal scenes, every technological requirement is amplified, including the need for robust and reliable timecode.

In the case of Avengers 2: Age of Ultron, creating the spectacular scenes and VFX we’ve come to expect from Marvel, involved developing solid workflows for a large number of very large multi-camera set ups. For some shots, as many as 12 cameras were rolling with a total camera package of 27 cameras including ARRI Alexa XT’s, Canon C500s with Codex Recorders, RED Epics and Blackmagic cameras. The huge amounts of data generated, made embedding accurate, perfectly synced timecode into every piece of footage an important technical requirement.

“A big part of my role is to anticipate it all going wrong,” Welch adds. “With this shoot, there was a chance that cameras could be taken out while filming, putting footage at risk of being lost.”

While the Alexas were strategically rigged a safe distance from the main action, the C500s were placed in and around the explosion, putting them at an increased risk of being caught in the line of fire.

“One of the largest action sequences for Age of Ultron was filmed in Korea with eight cameras rigged to capture footage – four ARRI Alexas and four Canon C500s,” Welch says. “There was huge volumes of RAW output going to Codex recorders.”

As an added complication, once the set was built, and definitely once it was hot with explosives, they couldn’t go back in to adjust camera settings.

Whilst Welch was able to manually jam sync the Alexas, the C500s had to be set to record with timecode running at the point of rigging. There wasn’t an opportunity to go back later and re-jam midway through the day, they had to stay in sync throughout, whatever twists and turns the filming process took.

With the C500 cameras placed in strategic positions to maximise the action, the Codex recorders, Preston MDRs and power were built into recording and camera control boxes (or ‘safe boxes’) and positioned at a distance from the cameras and then connected via a bespoke set of cables. Within each C500’s ‘safe box’ he also placed a Timecode Systems timecode generator set in receive mode. This was synced over RF to a master unit back outside of the ‘hot’ zone. This was left running throughout a long shooting day with complete confidence and no requirement for manual jamming or resetting. This set-up ensured all footage captured by the C500s in the ‘hot’ zone was stamped with the same frame accurate timecode as the Alexas. The timecode could also be monitored via the return video signal’s embedded SDI feed.

But it’s not just the pyrotechnics that inject unpredictability into shooting this kind of scene – the sheer scale of the locations can be as much of a challenge.

“Whatever system we build for an action sequence, it has to be reliable and flexible because you can never second guess what’s going to happen next,” says Welch. “The ability to synchronise timecode over RF definitely helps as there is always a chance a camera could be taken further away than we have control of.”

Although it’s possible to fix sync problems in post-production, it’s time consuming and expensive. Getting it right, as Welch did, at the point of shooting offers considerable efficiencies to the production process. Something that every production demands – even those working with Hollywood-sized budgets.