Isolating Camera Vehicle Motions

Every vehicle and support system has different motions to isolate from the camera. Any reduction of unwanted vehicle movement helps the camera system work better. Camera cars use the mass of the turret and weight box to help stabilize the camera, operator etc. Lightweight remote head arms on camera cars are improved by a spring-loaded vertical shock absorber on the post that helps isolate road bumps from the arm. Jim Dickson does this. As vehicles and dollies go over bumps there are various motions that inertially stabilized mounting of the camera about its CG and tripod head will improve. (See Professional Rigging Inertial Tripod Head)

Factors: 1. If the camera is relying on the inertia of a vehicle for stability, the camera and tripod or rigged support needs to be well supported to the vehicle so that the camera doesn't move separately from the vehicle. Weak tripod legs supported on flexible metal panels or a tripod head that is too small doesn't help. Of course the tripod or camera support rigging needs to be well tied down. For a tripod it is best to tie it down at the bottom of each leg if possible.

2. Focal length is very important. A 1-degree shake would hardly be seen on a 60-degree wide angle shot, but a disaster on a 3-degree telephoto shot. A level and steady horizon is important. Horizon correction is handy. A strong ball leveling head helps. The camera can usually bounce up and down vertically and not be objectionable if the horizon is stable in the frame. (See Professional Special Effects Feeling of Motion)

3. A camera high above the wheels of a dolly rocks back and forth as a wheel goes over a bump on dolly track or on the ground. If the camera is on top of a fluid head with counter balancing springs, the camera tips because the C of G of the camera is above the pivot point of the fluid head. The Chapman Vibration Isolator will eliminate this motion. A gear head, strong nodal head (Weaver Steadman) or (see Professional Rigging Inertial Tripod Head) described in this site will reduce or eliminate this motion. The wider the spread of the wheels of any dolly the less bumps on the track or on the ground will effect the camera. A narrow doorway dolly with a high camera will sway a lot on grass or rough ground where a wider wheel dolly will be much more stable. Attaching/tying down the tripod spikes as close as possible to the wheels helps eliminate any flex in the dolly frame such as a plywood skate board model or one made out of go-cart wheels. Consider a modular go-cart wheel dolly made out of Speed Rail © to allow a wide adjustable wheel base. Also provide support for the operator so his body doesn't bounce around. It will help him judge stability of the shot and prevent his body motion effecting the smoothness of the shot. Apple boxes tied to the dolly to sit on will help.

Cars: Old luxury gas-hog sedans and station wagons are very stable. Taking a Sawsall or cutting torch to one can create an ugly but stable camera car. They won't support an arm for the operator and assistant but might support a remote arm. A professional camera car is designed to provide room for everybody to work. With a camera car you also get (almost always) an experienced driver that is aware of safety and knowledge of what can be done reasonably and efficiently. Some trucks are well sprung and can be used. Weight helps smooth out stiff suspensions.

4. Large Ships roll slowly enough that a pendulum tripod system like Tyler's or Clairmont's will compensate for the slow rolling with simple gravity. Sometimes an operator can compensate for the ships rolling if shooting objects broadside off the ship in calmer seas. On a set, a "Dutch" head will help recreate the rolling effect.

5. Smaller Boats roll about an axis approximately around the center of gravity and hull curve of the boat, but at a higher rate than a pendulum system can compensate for. An operator supported inertial system can work in some conditions. (See Inertial Camera Stabilization The Horse Collar) A camera on a tripod is not very useful at very much speed or on a rocking stationary boat. For flat water two flat bottom duck boats lashed together with strong beams is very stable. "Vee" hulls like catamarans are not as good as lightweight flat bottom boats. The wider the boats or hulls are, the more stable the platform is. Consider an outrigger off of one boat. It could be a plank floating flat in the water. Use stiff beams to support it to avoid motion between the boat and outrigger. (See Professional Production Technique Shooting on Water)

6. Airplanes suffer mostly from air disturbances that rock the plane about its fuselage axis. This shows up most on the horizon in camera. Wider lenses helps and shooting higher speeds helps. A STOL like the Helio Porter with long wings is much more stable than a Cessna piston plane. Rigging a camera support securely to the floor or seat rails of the plane helps. There are cargo tie-down clamps that attach to seat rails on the floor. You can also make tie down clamps out of angle aluminum, bolts and "S" hooks. Removable cargo doors such as on a Cessna 206,207 or 208 models make shooting out the side easy. Wind deflectors are FAA required when flying with the cargo doors off and to reduce airflow through the plane. (See Professional Rigging Technique Shooting out of Small Planes)

Shooting early AM helps when the air is usually smoother and the light is better too. An intercom with the pilot and/or director is very helpful. Dress warm, carry maps and discuss before take-off with the pilot what you are looking for. I found it easier to explain changes to the last shot you just tried easier than trying to describe a whole new shot.

7. Helicopter bodies oscillate below the supporting blades. Bigger ships are more stable. Tyler mounts and gyro stabilized systems work well. Well-balanced helicopter blades help. The more blades the smoother the ship and clearance below the shorter blades is increased especially with forward motion. (Hughes) Crop dusters don't worry much about balancing their blades and often don't understand much about camera moves.

8. The Human Operator's body drops and rises in height as he walks. The smaller the steps the smaller the drops. There is also a front to back motion and if the operator's eye is against the eyepiece that can also introduce motion to the camera.

9. The mass and inertia of Chapman cranes and Fisher and Chapman dollies help stabilize the camera. The risers and extension arms supplied by them are usually strong enough if used properly. If you offset or extend an arm, balance the camera weight with a counter weight. It will reduce the strain on the dolly and make the camera more stable. 1-1/4" Speed Rail © isn't strong enough to support heavy cameras and heads as extensions. 2" IPS aluminum pipe starts to be strong enough. 1-1/2" steel pipe is strong enough. (See Professional Rigging Technique Pipe, Tube and Conduit)

10. Bicycle Wheeled Vehicles are lightweight and can work where other vehicles are not allowed such as on running tracks. Consider trailers or three wheel rigs. Bicycle wheels with 3/8" or 5/16" axles must be supported from both sides. Older coaster brake wheels can be outfitted with internal ball bearing and large enough shafts to be supported from one side only. Wheel chair wheels and industrial wheels can be supported from one side. 1-1/4" Speed Rail © is very useful to build these vehicles. Old bike frames can be cut up and welded. The peddle crank housings can be joined with tube and long threaded rod in the middle.

Bicycles are well designed to be ridden, but it is a challenge to rig a heavier camera on them. Consider all the shots that could be done from a regular dolly, golf cart, rigged side car or car with a bicycle being towed along side or behind.

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