Compare this to the fourth axis solutions currently available for motorised gimbals. Most of these are very rudimentary "Steadicam alike" arms that protrude out horizontally from the gimbal frame, and have to be held by two hands. They do an okay ish job at isolating bob, but they are way far from perfect, and that's because they bounce a lot, and continue to bounce long after a violent movement has stopped.
In addition there is currently nothing to compensate for sway other than the operators own arms. Solving the problem will involve a lot of engineering complexity, and maybe extra motors rather than just a spring loaded arm. But if gimbals are to truly be a full stabilisation solution, these issues must be solved properly. But there's one more thing. Another big factor in why a Steadicam is so good is the simple directional control over the camera.
It's a fully tactile affair through the fingers of the control arm, and, like most other things in the world of Steadicam, it is extremely difficult to do well.
But it is an obvious thing to do, even if you are no good at it. Rotate the central column of the sled for pan, push or pull with your little finger to control tilt. Focus control still needs to be outsourced to another crew member generally. This allows actors to be followed with critical framing, but also allows a lot of versatility for direction changes. A Steadicam operater can, for instance follow an actor in one direction, and then as another actor passes in the completely opposite direction they can turn their bodies degrees while leaving the camera facing in its original direction, but start physically moving the other way.
This is a move that is pretty much impossible with a gimbal. At least not easily at any rate unless you want to be pressing buttons mid-shot to change follow modes depending on what happens later in the shot. With a gimbal, effectively you need another crew member to motion control the camera direction, and yet another to focus control. Most gimbals do have some sort of mini joystick control, but it is rarely accurate or truly useful, or you have to work around the way the camera follows where you are pointing the gimbal itself.
Not always convenient or easy. Instead, on a single handed gimbal for instance, the central column should perhaps have a tactile style 'rotation sleeve' that allows direct transfer of rotational input from the fingers to control pan, and pressure sensitivity to allow control over tilt. It would be a much more intuitive way of control it. This could also be done on control handles for two handed systems. A joystick simply isn't a good solution. Where there's a will, there's a way, and I'm sure that if the gimbal manufacturers took these issues seriously a solution could be found that doesn't involve bulky spring loaded arms.
It might need some sort of extra inertia sensors to pass on information to extra motors, or maybe even a form of belt drive system for the vertical bobbing axis so that the motor can compensate rotationally in the same way the other axes do.
I'm not an engineer so it's all very easy for me to suggest this stuff without having to come up with a practical solution. What I do know, however, is that a solution really does need to be discovered, because if you want the best stabilisation, thanks to new innovations owning a Steadicam that is much easier to learn to control than the past is gradually becoming a firm reality.
Gimbals watch out! Tags: Production. RedShark is a multiplatform online publication for anyone with an interest in moving image technology and craft. Second, the combined weight of the camera and the base gives the whole unit relatively high inertial mass. To move the camera, the operator holds the post by the gimbal handle. Worth pointing out, controlling the whole system requires very light touches.
Some of the advanced units also have a wireless remote for lens adjustments. This minimizes the chances of shaking the camera even further. Besides adding to the bottom weight, the monitor also takes over the role of the viewfinder. This is because the latter becomes practically unusable at some shooting angles. The arm connects the Sled and the Vest.
The arm comprises 2 parallelogram segments joined by a pivoting hinge. These metal blocks have a spring that connects the top and the bottom bars. Each of the metal blocks also has a knob. Its role is to adjust the spring in relation to the weight of the camera. Simply put, the arm functions as a shock absorber.
It smoothes out any sharp jolt so that the camera shifts the position smoothly. When properly tweaked, the arm can comfortably support the camera independent of the operator. Primary weight transfer is around the pelvis, the chest area, and on the shoulders. Notably, these regions are heavily padded.
Crucially, these heavy pads help in balancing the rig. Are you in need of the best steadicam models for DSLR in ? In this way, the arm and the camera sled will stay in the same position until the cameraman shifts the camera up and down. In the original Steadicam design, the bars were connected directly with springs. In the modern Steadicam, the arrangement is a little more elaborate, but it serves the same function.
You can see how this system works in the illustration. The lower bar in each arm segment is actually a hollow cylinder, with a large coiled spring inside. The spring is attached to a pulley, which is connected to a drum by a pair of metal cables.
The drum, in turn, is connected by a cable to the opposite end block. In this configuration, the spring pulls the pulley back, which rotates the drum, which pulls the cable attached to the opposite end block.
In this way, the strength of the coiled spring works to move the parallel metal bars opposite the force of the camera's weight. The advantage of this system is that it's easy to adjust the spring strength to match different weight loads. The cable can be moved up and down on the end block.
Moving it up rotates the drum, which pulls the pulley in closer, which stretches out the spring. This increases the pulling force working against the weight force. The articulated arm essentially acts as a shock absorber for the camera sled.
When the operator moves, the base of the arm moves as well. But the spring system in the rest of the arm responds to the weight of the sled. Instead of a sharp jolt, the camera shifts its position smoothly. The arm also frees up the person's hands -- it hangs directly on the vest, so the operator doesn't have to do anything to hold the camera sled up. He or she can concentrate on positioning the camera to get the best shot. The Steadicam sled is the assembly that actually holds the camera equipment.
A Steadicam operator moves the camera by rotating and tilting the sled pole , the central piece of the sled, which connects the various camera components. In the standard configuration, the monitor and battery are attached to the bottom of the sled pole , and the camera is attached to the top. Some Steadicams are reversible, so the cameraman can position the camera on the bottom and the other components on top.
This makes it easier to get low angle shots. In addition to moving with the pole, the camera can be pivoted up or down on its mount called a sleigh , and in some Steadicams, the pole can telescope up and down. This lets the cameraman get high angle shots. Other than holding the camera equipment, the sled's primary job is to provide balance.
It achieves this by increasing the camera system's moment of inertia , or how resistant it is to rotation. This is determined by two factors: how much mass the object has and how far that mass is from the object's axis of rotation. Increasing mass makes an object harder to rotate, as does increasing the distance between the mass and the axis of rotation a rolled out slab of clay, for example, is harder to rotate than a tight clay ball with the same mass.
Increasing the object's moment of inertia makes it harder to shake the camera unintentionally. One way to increase the moment of inertia would be to add more weight to the camera system, but this would make things harder for the cameraman. Instead, Garrett Brown decided to take the existing components of the camera and spread them out.
This increases the distance between the axis of rotation and the mass of the total camera assembly, making the camera more resistant to rotation. Expanding these components also shifts the camera assembly's center of gravity , or the point where the object's weight is balanced.
When you hold an object precisely at its center of gravity, you can lift the object straight up because the downward pull of gravity is equal in all directions. You can balance a broom on your finger, for example, if you lift it at just the right spot between the bristles and the center of the broomstick. But if you place your finger anywhere else along the broomstick, gravity will pull more on one side than the other, and the broom will fall over.
In an ordinary camera assembly, the center of gravity is inside the camera itself. When you spread out the components, the center of gravity falls between the various pieces of equipment, along the sled pole. In a Steadicam, the articulated arm's gimbal grips the sled pole just above the center of gravity, in order to keep the camera from tilting in any direction on its own.
The cameraman typically grips the sled pole at a point near the center of gravity, allowing him or her to control the camera more precisely. Balancing the sled components correctly is a precision operation.
The camera, monitor and battery have to be positioned just right so that the center of gravity falls near the gimbal. To make this adjustment easier, sophisticated Steadicams are outfitted with radio-controlled motors that move the various components by minute increments. This makes it easier to balance the sled when the cameraman is getting ready for a shot, but it also allows the cameraman to make adjustments in the middle of a shot.
This is an important feature, since the sled balance often changes during operation for example, the weight of the film will shift as it moves through the camera. For some shots, the cameraman may want to shift the center of gravity away from the gimbal, so that the camera leans in one direction on its own.
The balance can be adjusted with a joystick mounted on the sled grip, or remotely, with a radio-control unit. In the next section, we'll see how Steadicam operators put all this technology to work to get remarkably smooth, hand-held shots.
Operating a Steadicam is one of the most difficult jobs on a movie set , but perhaps one of the most rewarding. For a typical Steadicam shot, a camera operator must follow a predetermined path, while simultaneously adjusting the camera and avoiding any obstacles, all the while supporting more than 70 pounds 32 kilograms of camera equipment.
The Ultra 2 model's iso-elastic arm has a camera capacity of up to 70 pounds. The job requires a good deal of physical stamina, technical skill and a good sense of shot composition. The director plans the shot, but the Steadicam operator makes it happen. The best technique for Steadicam operation depends on the nature of the shot. To film a simple conversation between two actors, an operator may try to replicate the even feel of a dolly shot, keeping the camera perfectly level and moving it slowly around the action.
For a "flying sequence" over low ground, the operator might intentionally tilt the camera from side to side, creating a soaring effect. One of the most common uses of the Steadicam is to track actors as they move around obstacles or rough ground. Typically, the operator will walk ahead of the actors, shooting them from the front as they walk and talk. For this sort of shot, the operator may walk backward through the scene, with the help of other crew members.
Or he or she may walk forward, with the camera pointing behind him or her. Or, heck, he or she may hop on a Segway traveling at a good clip, dismount, sprint up a ramp and then do a around the point of interest see the related YouTube video here. For these shots, and most any other, the director , the crew and the operator will all work together to figure out the best approach.
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