This present disclosure relates to a motion control device, such as a slider, suitable for moving an object, such as a camera, along a defined path. Sliders are well known in the photographic and cinematographic arts. A slider is typically defined by a rail system having a pair of parallel rails with a slider tray carried on the rails and a camera is mounted to the slider tray. Sliders are useful for producing a camera shot where the camera needs to be moved along a defined path. Sliders may define a straight or curved path, and allow for a smooth and repeatable camera movement. It is common for motors to drive the slider so that the slider moves at a defined rate along the rails. Such motors are capable of providing precise movements at variable speeds.
In some instances, it is desired to have the camera not only move along a defined path, but to also have the camera pan as it moves. Previously, panning required use of a motor which rotated the camera at a precise rate and a precise time relative to the motion of the slider as it moves on the rails. Such motors are expensive and require a high degree of skill, and considerable time to program for a given shot to ensure the camera pans and slides in unison.
One common camera movement which illustrates the difficulty of coordinating the pan and slide movements is a “fixed point shot.” In such a shot, the desired effect is to have the camera remain focused on a given stationary point spaced some distance from the slider as the camera moves along the rails. In order for the camera to point at the given point during the travel along the rails, the camera must rotate at a rate such that at any given position along the rails, the camera is pointed directly at the given point. While previous slider systems are capable of producing such a shot, they are only able to do so if set up by a highly skilled technician who carefully calibrates each of the respective motors. Therefore, an improved panning slider is needed.
The present disclosure describes a rail system having a pair of parallel rails for moving and panning a camera or other photographic equipment during a photo shoot. A carriage rides on the rails along a path defined by the rails. The rail system includes a guide member which is positionable independent to the pair of parallel rails. The carriage includes a table which is rotatably mounted on the carriage; the table is also mounted to an arm which rides on a carriage, which carriage is carried by the guide rail. In this way, the arm causes the table to rotate as the distance between the guide rail and the parallel rails changes, which rotation causes the camera to pan. One embodiment of the pan system pivots the guide rail at or near the center of the guide rail. This prevents the mean position of the guide being overly close or far away from the carriage. If the guide rail is too close or too far away, the assembly might bind at certain points in the linear travel.
Another embodiment involves the guide rail that is skewed to the parallel rails in two axes. The table is attached to the carriage such that it has more than one degree of freedom. This would allow the camera to pan side to side and up and down. This could be particularly useful if the camera needs to follow an object that moves in relation to the camera. At times, it may be desirable for the guide rail to be non-linear. This way a variable point can be followed as the carriage travels along the parallel rails.
The degree of the pan is dictated by the angle of the guide rail. In this way, the present disclosure describes a rail system which pans a camera as it moves along a rail system without the use of a pan motor.
A preferred embodiment of this invention has been chosen wherein:
The present disclosure describes a rail system 10 having a pair of parallel rails 12, 14 as shown in
One advantage of the present rail system 10 is that it is suitable for use in any orientation. The spanning members 19 include apertures which allow the rail system 10 to be mounted to any suitable surface, be it a horizontal surface like the ground, a vertical surface like a wall, or any other suitable surface. Typical panning systems use motor-driven rotation for the camera, and such motors typically aren't engineered to be used in any orientation other than horizontal (the motors are typically not rated to pull against gravity when panning) The current system does not rely on a panning motor. Instead, the current system pans as the slider moves, thereby, the system which moves the slider also causes the panning action through the mechanical system. In this way, the present rail system 10 provides significant improvements and versatility as compared to previous slider systems.
The rail system 10 includes a series of supports extending perpendicularly away from the parallel rails, preferably three supports 18, 20, 22 as is shown in
A table 38 is mounted to the upper surface of the carriage 16 such that the table 38 is rotatable relative the carriage 16 as is shown in
As is shown in
As assembled, when the carriage 16 is moved laterally along the parallel rails 12, 14, the linear bearing will move along the guide rail 24. The carriage 16 can either be driven manually by a handle 52 or with a motor. The handle 52 connects to a drive pulley 60 which is mated to a drive belt 62 as is shown in
One application of the present invention is to mount a camera (not shown) to the table 38, such that as the camera travels along the parallel rails 12, 14, the guide rail 24 can be positioned at a preferred angle which will cause the camera to pan at a preferred rate as the carriage 16 moves along the rails 12, 14.
As previously described, the outer supports 18, 22 are rods which are joined at one end to the frame 17. Respective slidable clamps 26, 28,
The middle support 20, as mentioned, includes a pivot member 36. In the preferred embodiment, the pivot member 36 is mounted a fixed distance from the parallel rails 12, 14 as is shown in
One sliding and panning move that the rail system 10 is specially adapted to provide is a fixed point shot. The fixed point shot is set up by first moving the slidable clamps 26, 28 to a position where the guide rail 24 is parallel with the parallel rails 12, 14, and centering the linear bearing 46 above the pivot member 36, as illustrated in
The rail system 10 illustrated in the Figures is shown as a linear rail. It is anticipated that the present three-rail system could be used with either linear or curved rails to achieve the mechanical panning described herein. The carriage 16 is moved relative the frame 17 by any means known in the art, such as by a motor, by a hand crank, by hand, or by any other suitable system. It is also possible to have only the outer supports 18 and 22 as supports for the guide rail 24.
The outer supports 18, 22 are joined to the frame 17 by respective mounts 48, 50,
The crown 34 is pivotally mounted to the respective slidable clamp 26, 28 to allow the guide rail 24 to move to the prescribed angle relative the parallel rails 12, 14.
It is understood that while certain aspects of the disclosed subject matter have been shown and described, the disclosed subject matter is not limited thereto and encompasses various other embodiments and aspects. No specific limitation with respect to the specific embodiments disclosed herein is intended or should be inferred. Modifications may be made to the disclosed subject matter as set forth in the following claims.
This application claims the benefit of U.S. Provisional Application No. 61/816,218, filed Apr. 26, 2013, the disclosure of which is hereby incorporated by reference.
Number | Date | Country | |
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61816218 | Apr 2013 | US |