Using Mass and Drag to the Fullest

When we first came up with the idea to use motors to change the mass of the wheels, I had no idea how it would be used or even what it would feel like. After two years of handling prototypes, designing motors, using them on set, and listening to customer feedback, it’s safe to say they feel amazing, and they are also a powerful, if still unknown, tool.

People think adjusting the mass and drag is just about finding what you’re comfortable with. But the more I’ve used the Inertia Wheels, I’ve learned how to leverage mass and drag to suit what the shot requires. It’s made me a better operator.
-Graham Futerfas, Operator/Inertia Wheels Owner

Today I want to share the collective wisdom from several hundred customers that now use the Inertia Wheels on set.

Part 2 of a series on physics from our founder, Boyd Hobbs. Read Part 1. Part 3. ❯

Mass is something we work with on set all the time. Camera operators and dolly grips, in particular, are masters of the laws of inertia. When they operate a lightweight camera handheld, manipulate a Steadicam in a complex move, or bring a heavy dolly to a gentle stop, they’re inherently leveraging inertia.

In the early days of filmmaking, cameras were heavy. The cranes, vehicles, and apparatuses needed to move them were even more significant. Stability was hardly a concern. Mobility itself was challenging. The cameras were so large and heavy that stability came naturally—even J.J. Abrams would have a hard time shaking them.

Over the years, cameras have shrunk, and the film industry has learned when to use intelligent software and applied engineering to augment the simple stabilizing forces of a heavy camera. A Steadicam isolates the jostling forces of footsteps and allows the camera to maintain its own inertia. Stabilized remote heads use gyroscopes and accelerometers to hold a camera’s position.

The Inertia Wheels continue this tradition. But for the first time, they add stabilization at the input. They stabilize the operator’s hands. And they do it in a natural way that mirrors real, intuitive physics. Using a collection of technologies from ultra-high-resolution encoders, high-speed processing, and mathematical algorithms, the Inertia Wheels feel—drumroll, please—heavier... or lighter.

It may sound gimmicky at first to adjust the weight of the wheels. When applied to a single shot, it feels smooth. When applied to a shot list, though, something extraordinary starts to happen. That intuitive ability we all have to work with mass begins to leverage the weight of the wheels in new ways.

Now we’re seeing operators have conversations about what Mass and Drag settings to use for various shots. A whole realm of discussion emerges from suddenly having the ability to change the mass.

Personally, I like a seven on Mass and three on Drag (7/3) if I am following smooth, rehearsed marks. 9/0 is great if I’m trying to do an unmotivated camera move, like an establishing shot. If the move is has a lot of starts and stops, I might use 5/5. You can adapt the numbers and settings to your own taste, but overall, the ability to change the feel of the wheels has a powerful effect on the end shot.

And the more the wheels can help you achieve the shot, the more brainpower you can allocate to other details of the shot, taking your operating to unlimited new heights.