24
Dynamic Balancing the Steadicam
®
Sled
A sled is in dynamic balance when the
center post remains vertical as the sled is
panned (and this is critical) at any and all
panning speeds.
Dynamic balance is extremely important
for precise operating and for whip pans.
For each arrangement of camera, monitor
position, post length, accessories, etc.,
there are many possibilities for statically
balancing the system.
However, for each arrangement of
camera, monitor position, post length,
accessories, etc., there is only one
combination that balances the sled both
statically and dynamically. There is some
leeway as to the required precision of
dynamic balance. What is acceptable
depends upon the operator and the
situation.
Dynamic balance can very easily and
quickly be achieved by the trial and
error method.
In all cases, when a sled is in dynamic
balance, both the camera’s c.g. and the
battery’s c.g. will be to the rear of the
centerline of the center post. This rule
gives you some point to begin balancing
the system.
Advanced Techniques
Dynamic Balance
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over the post; the monitor and battery are on the same horizontal plane, and their
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It’s absurd, of course, but it makes a point. Now the common monitor and camera
c.g. is over the post, and the battery’s c.g. is directly under the post.
So you can see that as the monitor is raised, the camera c.g. must move to the rear
and the battery c.g. must move towards the post. With most sleds, the monitor c.g.
is raised above the battery c.g., therefore the camera c.g. is always to the rear of
the centerpost.
It typically works out that the camera c.g. is pretty close to .5in (12mm) to the rear
– a bit more if the camera is light or the monitor is higher, and somewhat less if the
camera is very heavy or the monitor is lower.
