The Steadicam® and Its Parts
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Section One the Steadicam® and its parts 7 11CC SSectionection final.inddfinal.indd 7 111/19/081/19/08 112:22:202:22:20 PPMM The Steadicam® Operator’s Handbook Wearing the Steadicam® for the fi rst time Q: What’s it feel like? A: Well, it’s different. Until you wear it once or twice, very little of what we’ll discuss in the book will make much sense to you. Q: Come on. What’s it feel like? Is it heavy? A: It’s going to be a lot less effort than you might expect. Q: Will it hurt my back? A: If the vest and arm are adjusted right, and you stand correctly, it will not hurt or strain your back. Q: So, what’s it going to feel like? A: You’re going to feel some pressure on your legs, but not much. The Steadicam is going to move around a lot more than you might expect. It’s very free to move in space and to pan, tilt, and roll. Very, very free. You’ve got to dance with the Steadicam and be in balance at all times. It helps if the sled is in balance, if you have a solid understanding of the physics, if you know what to do with each hand, how to walk, and... Q: What are you talking about? Am I going to fall over? A: Probably not. You’ve got to try it on, and the sooner the Steve Tiffen, at age 15, better. If you are at a workshop or demonstration, some- tries on the Model One one knowledgeable will help you get into the rig for the for the fi rst time at the fi rst time. If you’re on your own, then read as much as you Film 77 trade show. can, and when you feel comfortable, pick it up. It won’t kill you if everything’s not perfectly adjusted. After wearing the Steadicam Q: So that’s what it feels like. Amazing. Different. What’s next? A: Go back and read some more. Keep picking it up and practicing. Learn how it all works. Watch movies. Start dreaming of making shots. You have the tool. Learn to use the Steadicam well. The more experience you have, the more you will understand the concepts and ideas in the book and the more valuable the information will be to you. It’s going to be an amazing journey. 8 11CC SSectionection final.inddfinal.indd 8 111/19/081/19/08 112:22:232:22:23 PPMM The Steadicam® and its parts Basic physics a four part solution Understanding how a Steadicam solves the problems of “shakiness” will help you learn to balance and operate the Steadicam more quickly. Garrett always broke it down into the “four part solution.” Here’s another version of how it works: Handheld cinematography is alive with movement and quick to respond. This is useful for a rapid-fi re, inside the action feel and is implemented when appropriate for the story. Handheld has also been used as a way to visually express the point of view (POV) of a character. However, the intimate feel achieved with handheld is often shat- tered by unwanted and unrealistic movements. No matter how rough a trail becomes, the hiker’s brain maintains a smooth, con- tinuous view of the scenery, so why should our shots shake, rattle, and roll when walking down a trail? Handheld camerawork suffers from two kinds of unwanted movement. One is spatial, when the camera makes unwanted moves in space, such as the bounce with each step the cameraman makes. The other is angular, where the camera makes unwanted rolls, pans, or tilts during the shot. Angular solutions The problem: Most cameras are relatively compact, and therefore an operator can pan, tilt, or roll them rather quickly. In some respects a camera is like a bowling ball, easy to spin (move angularly) on any axis. Everything is fi ne when the camera is attached to a tripod, but when a living being attempts to hold this contraption, the problems begin to show up on screen. All contact with the camera is on the outside of the camera body — outside of the camera’s center of gravity (c.g.). The cameraman’s lifting and aiming forces are rarely directed through the c.g. of the camera, so the camera will turn or twist as well as move. Trying to hold the camera still, the operator creates both spatial and angular vibrations that disturb the shot. defi nition Center of gravity (c.g.): x that point in a body around which its mass or weight is It is impossible to get your evenly distributed or balanced hands on a camera’s cen- and through which the force of ter of gravity. gravity acts. 9 11CC SSectionection final.inddfinal.indd 9 111/19/081/19/08 112:22:242:22:24 PPMM The Steadicam® Operator’s Handbook On the other hand, when the handheld camera operator wants to impart a controlled an- gular motion to the camera (like a pan), the force required is very small, while the force required to lift the camera is very large. The operator must continually micro adjust the small panning forces, and he must use the same arms, hands, legs, and shoulders to do the heavy lifting. Good handheld operators have all sorts of tricks for smoothing out unwanted motions, but very quickly the range of acceptable smooth motions runs out and the camera shakes, vibrates, rolls, or bounces in an undesirable way. So how does the Steadicam work? First, the Steadicam adds several other masses to the camera body via a rigid structure. defi nition Two things immediately happen: The fi rst is that this new, heavier, and longer Inertia: n., physics object takes a lot more force to turn an- gularly. The second is that the new c.g. c.g. The tendency of a body can be touched by the operator. Grabbing to resist acceleration; the the object at the c.g. induces the least an- tendency of a body at rest gular change, or put another way, has the to remain at rest or of a smallest possible angular (shaky) effect body in motion to stay in on the image. motion in a straight line unless disturbed by an If we add masses to the camera in two external force. directions, it becomes more resistant to angular change in all three dimensions. We now have an object that resists turning (we can say it has greatly increased angu- lar inertia) and we can grab it at a spot that Adding masses via a rigid structure doesn’t make it turn very much. allows the operator to touch a new c.g. of the combined structure. We still have a problem though. We are still doing the heavy lifting (now even R O L heavier!) and aiming the camera with the L same muscles. This is the limiting factor of all shakicams. N PA T I The gimbal L T The next part of the solution is a three- axis gimbal placed near the new struc- ture’s c.g. If the structure is lifted by the gimbal, the lifting force will not affect the structure angularly. This is very important: The gimbal separates the large lifting force from the small “aim- ing” forces that frame the shot. Also, the gimbal allows the Steadicam to be balanced — and therefore aimed — independently of the lifting force. Why is this important? Although human beings cannot exert a constant force to aim or lift the camera, we can exert an average force of zero. If we combine our own “zero force” ability with a gim- 10 bal, we can achieve great precision aiming the camera. 11CC SSectionection final.inddfinal.indd 1010 111/19/081/19/08 112:22:282:22:28 PPMM The Steadicam® and its parts Spreading the masses and adding a gimbal gets us: • a heavier device that resists angular movement. • a device whose c.g. can be touched. • a device that can be lifted without inducing angular movements. • a device where the small forces needed to aim the camera are separated from the large forces needed to lift it. • a device that can be aimed by its balance. Alas, with this new device, the operator can no longer put his eye to the eyepiece. Because the eyepiece is so far away from the new c.g., the slightest pressure will introduce large angular movement to the new struc- ture. What’s needed is a high-brightness video screen mounted somewhere on the contraption for accurate framing. While we’re at it, let’s use the masses of the monitor and a battery as the extra masses we need to make our inert object. If we’re carrying the weight, we might as well make it work for us! By the way, when the Steadicam was invented, there were no video assist cameras for fi lm work, and the fi rst “green screens” were not much larger than postage stamps. Thankfully, things have improved. defi nition Isolate and lift Momentum: n., physics The product of a body’s The Steadicam system still has to solve two more problems. We need to isolate the new mass and linear velocity. contraption from our body’s spatial movements, and we need a good way to lift this camera and all the extra masses we added to it. The solution is a mechanical arm that frees the camera from our shoulders, and a specialized vest that distributes the weight of the device onto our shoulders and hips.