Most dollies are large, although there are fold-up versions that will fit in a personal vehicle, like an SUV, pickup truck, or Jeep. Dollies often require boards or tracks to be laid down to form a smooth running surface.
There are substitutes for professional dollies used for tracking. Wheelchairs, shopping cards, children's wagons, roller skates, or a pushed automobile. In such cases, use air-filled tires for smoother motion. Large tires, especially when under inflated, give smoother dolly movements. Do not secure the camera rigidly to most improvised dollies. Handholding often insulates the camera from vibrations.
When you need a tracking shot faster than what you can get from a dolly, use a motorized vehicle. An automobile, especially if it is equipped with a shooting platform, is extremely versatile. In general, the larger the car, the smoother the ride. Sometimes automatic transmissions are preferable, since manual shifting may create a jerky movement. Keep tire pressure low to smooth out the ride. The camera should be handheld to absorb automobile vibrations. It is easiest to achieve smooth camera movement if the car's speed remains constant and most difficult if the vehicle goes from a stop into motion.
Shooting in the same direction as the moving vehicle results in the motion appearing normally on the screen. Shooting at right angles to the direction of the vehicle makes the car appear to be going roughly twice as fast as it is. At intermediate angles, the speed is between these extremes.
When heavy, virtually immovable objects such as trains or ships must appear to be moving, the camera and the backing can be moved, or tracked, instead. A lamppost, positioned in front of the camera and attached to the dolly, helps the illusion. The relationship of background to lamppost and camera makes the camera appear to be stationary while the train seems to be moving. Caution: Don't show the ground or the wheels of the train.
The handheld camera was first experimented with during the era of Silent Cinema, with a boxing sequence shot on roller skates. However, not until the early 1960s with the New Wave in France and the new documentary film in the United States was the potential of the handheld camera realized. The extreme mobility of this camera permits following the action, achieving a feeling of intimacy impossible in a tripod or dolly-mounted camera.
Image stabilization devices can be used to lessen unwanted camera vibrations and jiggles. These range from specially headed tripods with a heavy weight suspended between the legs (effective for slow movements like those of a ship at sea) to a helicopter mount that will dampen fast vibrations such as those from a helicopter or plane. All of these are different ways of stabilizing the camera when unique types of tracking shots are needed.