In case of a well-balanced stabiliser (with proper drop time Drop time is essential for the dynamics of the stabiliser. It is the time it takes for the stabiliser post to first pass through the vertical after being released from a tilted position
The optimal drop time of stabilisers is usually from 1.5 to 2.0 seconds.
The drop time is independent of the starting angle (e.g. the times can be considered equal at 20 or 40°), similar to a pendulum clock.), the stabilising effect depends on the sensitivity of the gimbal handle: the smaller the frictional or rolling resistance of the bearings belonging to the axes of the gimbal is, the better it can isolate the camera from the displacement of the grip caused by the unintentional movements of the operator's hand or body. However, the more sensitive the gimbal handle is (that is, the more effective the stabilisation is), the more the stabiliser swings during the accelerations and decelerations (starts, stops, and turns), which is just as undesirable as the camera movement caused by unintentional movements and trembling of the hand. In addition, the more effective the stabilisation is, the less can the panning be controlled by the grip, and should the operator touch anything else on the stabiliser but the grip, the effect of stabilisation will only be impaired.
Although the extent of the swinging can be reduced by moving the common centre of gravity (COG) of the camera and the stabiliser vertically closer to the intersection point of the tilt and roll axes (that is, increasing the drop time, or in other words, the time of the swinging cycle), and then, as a result, smaller and smaller forces exercise torque on the axes of rotation during starting, stopping and turning, but before the ideal, small degree of swinging could be achieved this way, the camera and stabiliser system will become uncontrollable even when the smallest force is exercised on it: even the air-drags that affect the camera and the counterweights to different degrees can tilt the stabiliser, and with it, the required setting accuracy of the camera balance The problem of excessive precision required of the adjustment, when the drop time is long (the common COG is close to the pivot point), is well illustrated by the fact that, in the case of the HDSLR-4, turning the one-touch balance knob by 10 degrees results in a 0.0008 in (~0.02 mm) displacement of the balance platform, which at a drop time of 4 to 5 seconds, will notably upset the initially perfect camera balance. can fall into the range of hundredths of mm, which cannot be economically achieved in case of a device as complex as this one (especially not for the whole mechanism, since the backlashes accumulate), so constant, time-consuming readjustments would be required. In this case we are left with lowering the COG (that is, reducing the drop time) and the excessive swinging that results from it.
Almost all of the major manufacturers try to find some kind of solution for these problems, however, it also occurs that reducing the swinging is generously left to the skills of the steadi-operator, who is, in such a situation, confronted with the ruthless truth of Newton's First and Second Laws with regard to the movement of the camera. Should swinging be somehow properly reduced, the pan control and turning will then remain difficult, as the optimal damping is (or should be) by far lower for the Pan axis than for the Tilt/Roll axes.
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