CN1187886A - Reverse Film Projection System - Google Patents

Abstract

A reverse film projection system for use with a film having side-by-side printed images enables projection of a series of images in a forward direction and adjacent images in a rearward direction by moving the projection head and associated aperture plate and film guide relative to the sides of the lens and lamp housing which project the film images. In a first forward drive position, the projector motor drives the film in a forward direction, with the first aperture of the aperture plate and the associated first set of film images being aligned with the light path. When the projection is completed in the forward direction, the projection head is displaced laterally to align the second aperture of the aperture plate and the associated second set of film images with the optical path, and the projection motor is engaged in the reverse direction. For various film presentations, the drives that move the projection heads, the vane control and the film transport drive are microprocessor controlled with absolute frame numbers.

Description

Reverse Film Projection System

background of the invention

field of invention

This invention relates generally to the field of automatic projection systems for staging motion pictures. In particular, the present invention provides films with images printed side-by-side such that by moving the projection head and associated orifice plate and guides of the film relative to the sides of the lens and lampshade projecting the film image, in the forward direction (hereinafter referred to as A set of images is projected in the forward direction and adjacent images are projected in the backward direction (hereinafter referred to as reverse).

current technology

Motion picture projection equipment requires complex mechanical systems to drive the film through the projector to provide a smooth image projection. To achieve this goal, a very mature mechanical system has emerged after years of hard work.

Even for short themes, cartoons or other short films, the length of the movie can become very long. Feature films of average length require very large reels, and may use multiple reels shown sequentially on different projectors to form a complete full motion image film. At the end of such a film showing, the film must be rewound for the next showing. Rewind requirements limit the ability to automate film projection systems. Even if rewinding a film left in the projector door enables automatic rewinding only by rewinding, it takes a lot of time to rewind to its starting point.

In another approach, a highly sophisticated and mechanically complex continuous loop system capable of immediate replay of film was developed for some occasions. However, the high cost and complexity of these systems have prevented widespread acceptance at a reasonable price.

The principle of printing multiple images side by side on a single film so that one frame can be projected in the forward direction and a second frame in the reverse direction is known. European Patent Publication No. 0191559 to the inventor JOHNMOSELY illustrates this prior art. Early reverse projector systems provided the basic means of showing films continuously with one projector, without film rewinding, and without the complexity of endless loop systems.

To simplify the mechanical setup of the projector, thereby reducing costs and providing high quality image projection, the present invention provides an improvement of the reverse projector principle.

Overview of the invention

The film presentation of the present invention relies on a film comprising: a first set of images framed at intervals from a first side of the film, the set of images being projected through the film in a forward motion sequence; A second set of images spaced on opposite sides to form a frame, the images of this set are projected sequentially through the reverse motion of the film. The projection system includes: a lampshade arranged to focus projected light on a defined planar geometric position or aperture; and a lens arranged to be combined with a projection head by The aperture projects an image onto a screen, and the projection head is laterally movable from a first position for projecting film in the forward direction to a second position for projecting film in the reverse direction. The projection head includes a reversible drive mechanism for receiving film and selectively moving film in the forward direction when the projection head is in the first position and for receiving film in the reverse direction when the projection head is in the second position and optionally move the movie.

The projection head includes an aperture plate having a first aperture aligned with a first set of film frames and a second aperture aligned with a second set of film frames. The projection head is at the first position, the first hole of the orifice plate is aligned with the hole window, the projection head is at the second position, and the second hole of the orifice plate is aligned with the hole window. A projector base for moving the projection head is mounted on a linear bearing, and moves from a first position to a second position through a sliding hydraulic cylinder, and the sliding hydraulic cylinder can be driven pneumatically, hydraulically, or electromechanically.

Film take-up rollers in the plane of film travel are structurally mounted to said movable projector base for correct film run in said base first or second position when said projector base is moved by Movement from the first position to the second position or from the second position to the first position does not require manual adjustment of the reel or take-up roll system.

To accommodate tolerances in the reversible drive mechanism due to the engagement of the sprocket with the film aperture, the first and second apertures in the aperture plate are sized to prevent the Movement of the area where the movie is shown.

Brief description of the drawings

The features of the present invention can be better understood with reference to the following drawings:

Figure 1 is a perspective view of the system components including the projection head and associated projector base, lamp base, lamp housing, and projector lens;

Fig. 2 a is the film layout that the present invention is used, the image lateral displacement of forward and reverse transmission;

Figure 2b is a schematic diagram of the size of the holes in the hole plate relative to the film frame to compensate for dimensional tolerances in the drive of the projector;

Figures 2c and 2d show another embodiment of the example shown in Figures 2a and 2b;

Figure 3 is a perspective view of the system seen from the front left corner, showing the relative positions of the lamp base (LB), projector base (PB), film sending and receiving trays and related servo drives and film support roller systems;

Figure 4a is a perspective view from the rear left showing another view of the film support roller system relative to the film support roller system of the projector base;

Figure 4b is a front view of the system;

Figure 4c is a left side view of the system;

Fig. 5 is the schematic diagram that is used in the film layout of the present invention;

Figures 6a-c are software control flow diagrams for the automatic operation of the projection system under the control of a microprocessor-based controller.

Detailed description of the invention

FIG. 1 shows the mechanism configuration of the components of the present invention. A lamp base (LB) 10 provides a rigid mounting structure for the lamp housing 12 of the present invention and a support structure for other components. Projection head 14 is mounted on projector base (PB) 16, and projection head 14 is movable laterally from a first position to a second position, shown in phantom, with a lateral displacement D of about 1 inch. The components of the projection head include: a reversible drive motor 18 with associated drive pulleys 20 for the operation of the mechanical components of the projection head. The projection head performs a standard Geneva movement, which is a well known technique and will not be detailed in this disclosure. As indicated by linear bearings 24, the projector base is supported on linear shafts 22 by linear bearings at various locations. The linear shaft is mounted on a suitable bracket 26 in the base of the lamp. A hydraulic cylinder sliding driver 28 connected to the projector base and the lamp base drives the movement of the projection head from the first position to the second position. Standard pneumatic, hydraulic, or electromechanical drives are available depending on the application. The projection lens 30 is rigidly mounted to the lamp base in axial alignment with the light source in the lamp housing. The positioning of the lampshade and lens on the base of the lamp focuses the light on the aperture window, which is three-dimensionally defined in two-dimensional alignment with the aperture plate 32, which has two apertures, as will be described in more detail below. Lateral movement of the projection head aligns one of the two apertures with the aperture window, thereby providing the maximum intensity of focused light from the lamp housing for projection of the film image aligned with the aperture.

As will be described in more detail below, an automatically controlled light barrier 34 controls the light from the shade. As will be described in detail below, a microprocessor controller 36 controls the automatic operation of the system, including: the forward and reverse rotation of the motor 18, the hydraulic cylinder slide driver 28 to position the projection head at the first or second position, the movement and control of the light barrier Giving and receiving of films.

For the embodiment shown in the figures, the structure of the movie is shown in Figures 2a and 2b. A fragment of 200 is shown in a printed frame. Standard 70mm 5-perforation film was used in the embodiments disclosed herein. A first set of 35 mm image frames 210 is printed in the 35 mm span of the film and a second set of film frames 212 is printed laterally adjacent to the first frame. The printing of the first frame group is used to show the film image when the film is running in the forward direction shown by the arrow 214, and the printing of the second frame group is used to show the film image when the film is running in the reverse direction shown by the arrow 216. To runtime, project a movie image. The orientation of the picture of the frame is the standard reverse picture, as indicated by reference numeral 218 'R'. The film frame gap of approximately 0.9375 inches is consistent with standard 5-perf 70mm film.

Frames aligned for film forward run are spaced adjacent to first film edge 220 , while frames for reverse run are spaced from second film edge 222 . In the embodiment shown in Fig. 2a, the forward and reverse frames are arranged approximately laterally opposite each other. Those skilled in the art know that the frame size positioning alignment on the film is obtained from the leading edge of the film. Figure 2b shows the approximate dimensions of a film printed by the illustrated embodiment of the invention, characterized in that edge 222 is a leading edge. For reference, box 224 represents a standard 65mm 5-perf camera aperture having dimensions of 2.072x0.9055 inches. In the present invention, holes 226 and 228 (shown in FIG. 1 ) in hole plate 32 are spaced laterally 1 inch apart center to center. To accommodate dimensional tolerances of the drive mechanism between forward and reverse due to the dimensional difference between the intermediate drive sprocket teeth and the vertical height of the film aperture, the first and second apertures are reduced in size by the film frame. As shown in FIG. 2b, the image area 230 of the film frame has an extent of approximately 0.700×0.900 inches. To maintain the original image frame aspect ratio of 1.35, the apertures in the aperture plate were sized to provide a projectable image area of approximately 0.600x0.810 inches. The reduction of the vertical dimension PV on the orifice plate is one less than the optical image OV, which is slightly larger than the dimensional tolerance of the reversible transmission between the forward and reverse directions, so as to ensure that the correctly framed images are projected in the forward and reverse directions .

In another embodiment shown in Figures 2c and d, the printing of laterally adjacent frames is offset by an amount equal to the dimensional tolerance of the reversible drive mechanism in order to accommodate the display through the two apertures of the aperture plate 32, The size of the two holes determines the range close to the image area and reduces shading.

In another second embodiment, the installation height of the linear shaft 22 supporting the base of the projector varies by an amount from the shaft end close to the first position to the shaft end close to the second position, which is enough to compensate in the middle of the forward and reverse directions. The difference in size between the bottom of the sprocket tooth and the vertical height of the film hole. Translation of the projector base from the first position to the second position causes a vertical displacement of the projector base so that the projection head compensates for the shown film amplitude. The vertical dimension change requirement from the first to the second position is about 0.050 inches.

In the present invention it is not required to rewind the film with a reversible projection head, which constitutes a great advantage over the prior art. However, in order to provide the film storage capability of the large capacity discs and avoid the requirement of loading the film discs on the moving projector base, the present invention incorporates a novel film support roller system as shown in FIG. 3 . The forward film delivery tray 300 (which constitutes the reverse receiving tray) and the forward receiving tray 302 are rigidly mounted to the light base or the structure supporting the light base. The assembly of Figure 3 mounted to the lamp base is denoted by LB. Similarly, components mounted to the removable projector base bear the PB identification lettering. A first controllable servo motor 304 rigidly mounted to the light base support structure is associated with the first film reel and is connected to the drive pulley of the first reel by a drive belt (not shown) in the embodiment shown. 306. Similarly, a second controllable servo motor 308 is rigidly mounted to the lamp base, and drives a second film reel via a pulley 310 (not shown). In the embodiment shown in FIG. 3, the first film reel is installed perpendicular to the moving direction of the projector base, and the second film reel is installed parallel to the moving direction of the projector base. In another embodiment, both film reels are mounted parallel to or perpendicular to the base of the projector, for optimum placement within a projection cabinet, as will be described in more detail below.

For film running in the forward direction, film 312 is pulled by a first disc on roller 314, which is rigidly mounted to the lamp base, with an axis of rotation substantially parallel to the direction of motion of the projector base. For other embodiments where the first disc is mounted parallel to the direction of motion of the projector base, roller 314 is mounted such that its axis of rotation is perpendicular to the direction of motion of the projector base. The film travels from roller 314 to a second roller 316, which is also mounted to the lamp base and has an axis of rotation generally perpendicular to the direction of movement of the projector base. Rollers 314 and 316 are spaced apart from each other to allow 90 degree rotation of the film without twisting. The film travels from roller 316 to a third roller 318, which is mounted to the projector base with its axis of rotation generally perpendicular to the direction of motion of the projector base. Mounting of rollers 318 to the projector base allows movement of the projector base from the first to second position without affecting film feed, since the film running between rollers 316 and 318 is aligned with the direction of motion of the projector base. Rollers 316 or 318 or both have a spring loaded tensioner in their mounting to keep the film stretched as the projector base moves.

The film travels from the third roller 318 to the fourth roller 320, which is mounted to the projector base on the film drive and displaced laterally sufficient to eliminate interference with the projection as the film travels by rollers 318 to 320. Rollers 318 and 320 are mounted spaced apart from each other to allow about 80 degrees of rotation of the film without knotting. The film travels from roller 320 to roller 322, which is also mounted to the projector base on the film drive. The axes of rotation of rollers 320 and 322 are substantially parallel, and roller 322 is mounted high enough on the film drive to allow the film to rotate the remaining 10 degrees for proper alignment with its projection system.

The film is pulled through a projection system (not shown) behind the perforated plate and the film exits the projection drive system to engage pinch rollers 324 which hold the film in alignment with the projection mechanism. The film then travels to roller 326, which is mounted to the projector base with its axis of rotation substantially perpendicular to the direction of motion of the projector base. Rollers 326 are spaced from pinch rollers 324 to allow approximately 90 degree rotation of the film without knotting. The film is run from roller 326 to roller 328, which is mounted to the lamp base. As previously described for rollers 326 and 318, rollers 326 and 328 are aligned so that the direction of motion of the film is parallel to the direction of motion of the projector base, and rollers 326 or 328 or both are mounted on tensioned handles with tension springs. on, to keep the film stretched when the projector base moves. The film is run by rollers 328 to the second film reel 302, which is a receiving tray for the forward run of the film. For the reverse film run direction, the path of the film is reversed, tray 302 is the sending tray and tray 300 is the receiving tray. In each structure of the projection cabinet where the second disc 302 is installed perpendicular to the direction of movement of the projector base, an additional roller is mounted on the lamp base, its axis of rotation is approximately parallel to the direction of movement of the projector base, and this additional roller is mounted at a distance from the roller 328. , allowing the film to perform a 90 degree run rotation before being received on the second reel 302. As previously mentioned, if it is desired to mount the first disc 300 in a direction perpendicular to the direction of motion of the projector base, the rollers 314 are mounted with their axis of rotation perpendicular to the direction of motion of the projector base, or the rollers 314 can be eliminated and the film directly fed from the first A disc 300 runs to roller 316 . In the illustrated embodiment, two film reels are mounted under the lamp base and projection head without interference from the upper reels, allowing the projector to be positioned high in the projection room for projections over the theater audience with minimal vertical clearance .

Figure 4a provides another view of the film receiving system showing the relationship between the rollers and the delivery and receiving trays. Figures 4b and 4c also show other diagrams of the film running system, including the structural outline of the projection cabinets that enclose the entire projection system. The arrangement of the present invention enables the projection system, film storage and guide components to be compactly installed in a single closed projection cabinet, and the filtered inhaled air prevents damage to the film and components, forming a good control of both the projection system and the film operation environment.

As previously stated, the present invention is capable of automatic continuous operation using a microprocessor based controller that automatically controls the servo torque motors, feed and receive pans, reversible projection head motors, projector base positioning drives and stoppers. Operation of light panels, etc. In operation, the microprocessor operates as follows. The operator activates with a starter key or type device and the microprocessor turns on power to the forward film reel servo torque motor to provide the proper tension for pulling and receiving. Then at step 612 of Figure 6a, the microprocessor directs the operation of the forward motion projection head motor to mix the soundtrack for the film in conjunction with queuing SMPTE or other time codes to any sound source. Then in step 614, the microprocessor monitors the film frame number provided by the counter integrated with the projection head to obtain a frame number indicating the start of the show. The show start indication corresponds to the start picture frame number of the movie in motion. At step 616, the controller commands the shade shutters to open, and at step 618, the show continues as the microprocessor monitors a frame count indicating completion of the show. It is known in the art that several separate films can be performed when projected in the forward direction.

At step 620, when the number of stops is reached, the microprocessor controller closes the shutter and stops the projection drive motor and reel servo torque motor. The microprocessor then instructs the projector base driver to move the projector base from the first position to the second position for reverse operation. The projector motor and the receiving and ejecting disc torque motors operate in reverse at the command of the microprocessor controller, and the microprocessor controller monitors the number of frames indicating the start of the reverse projection. When the correct frame number is received to start the show, the microprocessor instructs the shutter to open and the film is projected in reverse. The microprocessor monitors the number of film frames indicating the stop of the projection, and when receiving the frame number indicating the termination of the reverse projection, closes the lampshade baffle, stops the projection head motor and the servo torque motor of the film receiving tray. The microprocessor then instructs the driver to move from its second position to its original first position, enabling forward travel. The projection head motor, the servo torque motor for receiving and sending out discs are operated in the forward direction by the microprocessor, and the forward film program is replayed. Such continuous operation continues until a system stop signal is received by the operator.

The details of the synchronization of the frame count and microprocessor controlled operation will now be described further with reference to Figures 5 and 6a-c. Figure 5 shows the image arrangement of the forward and reverse film laterally adjacent, with the forward frame numbers for the forward film frame counters for showings 1 and 2 and the reverse frames for the reverse film frame counters for showings 3 and 4 Number signs: empty lead 400, black lead 402, show start (frame) number S and film frame P. Those skilled in the art know that four screenings can be used as an example, but multiple screenings can be performed in each film direction. For the sake of simplicity, the lengths of showings 1 and 4, and showings 2 and 3 in the figure are chosen to be equal, and showing 1 is represented by 35, and showing 2 is represented by 23. To get equal lengths in forward and reverse, projections in one direction or the other can fill in the leads so that equal forward and reverse frame numbers are formed.

As shown in Figures 6a-c, at step 600, the microprocessor controller monitors a keyboard or other device for operator input selecting unidirectional or bidirectional operation. In step 602, the operator enters the number of showings, and the corresponding show lengths of the films loaded into the system. In step 604, the microprocessor controller calculates the overall show length (TSL) by adding the individual show lengths entered by the operator. In this example, the overall length of 35, 23, 35 and 23 is 116. In step 606, the microprocessor controller divides the total show length by 2 and rounds up to obtain a counter length (CL) to determine the forward and reverse counter lengths. In operation, if the count value is less than CL, the projection will proceed forward; if the count value is greater than CL, the microprocessor will drive the projection head and supporting motors in the reverse direction. Those skilled in the art will know that the film frame counter can be zeroed when the orientation is reversed, as opposed to being zeroed when the reverse projection end count is reached.

The inversion process is done by the microprocessor controller. When the film frame number indicates that the film position is about 6 feet from the upside-down count, at step 622, the microprocessor controller places the projection head in a self-stop mode. At step 624, this mode decelerates the projector motors and advances to the reverse frame count. At steps 626 and 628, when the frame counter indicates one frame from the reverse orientation, at step 630 the projector motor is turned off by the microprocessor controller. On frames with an upside-down orientation, the movie slides, but should actually stop. Then at step 632, the microprocessor controller completes the movement of the projection head, and operates in reverse.

To mark the control points of the film inversion process, as an alternative to using frame counters or in combination with frame counters, the microprocessor controller can utilize a system of physical markings on the film surface in combination with a gauge. As shown in FIG. 3, a metal strap 330 is placed on the film which prevents the light source 332 from entering the receiver 334 at a desired control position. Those skilled in the art will know that a reflective system with a light source and receiver on the same side of the film can be used as an alternative. Physical markers on the film are used to generate an external signal instead of film count determination, which is used by the microprocessor to generate a control function. A number of physical markers can be added to the film to signal film orientation reversal, including projection head movement in steps 648 and 650 shown in Figure 6c, shutter opening in steps 640 and 642 and shutter closing in steps 644 and 646. In other embodiments, the physical markers on the film are also used to initialize a frame counter or other timing device within the microprocessor to perform the desired control functions.

The present invention has been described in detail in accordance with the relevant provisions of the patent statutes. Minor substitutions and modifications to the embodiments in this description will be made by those skilled in the art. These modifications and substitutions are within the scope of the invention as described in the appended claims.

Claims (16)

1. A film projection system, comprising: A film comprising a framed first set of images spaced from a first side of the film, the set of images being projected through the film in forward motion sequence; and a framed second set of images spaced from a second side of the film two sets of images, the sets of images being projected sequentially through reverse motion of the film, the frames of said second set being substantially horizontally adjacent to the frames of the first set; a lampshade arranged to focus projected light on the perforated window; a lens arranged to project an image from the aperture onto a screen; A projection head, movable from the first position to the second position, and has a film drive mechanism for receiving film forward and selectively moving film when said projection head is in a first position and for receiving film and selectively moving film in reverse when said projection head is in a second position, an aperture plate having first apertures aligned with a first set of film frames and second apertures aligned with a second set of film frames, in a first position of the projection head, the first an aperture is further aligned with said aperture window, said second aperture is aligned with said aperture window in a second position of said projection head, and means for moving said projection head from said first position to a second position. 2. The film projection system of claim 1, wherein the second set of frames of the film is vertically offset from the first set by a predetermined amount to compensate for intermediate chains in forward and reverse directions. The dimensional difference between the bottom of the wheel and the vertical height between the perforations. 3. The film projection system according to claim 1, wherein the second position of the projection head is vertically displaced by a predetermined amount from the first position to compensate for the teeth of the intermediate sprocket in forward and reverse directions. The dimensional difference between the vertical height between the base and the perforation. 4. The film projection system according to claim 1, wherein the first hole of the orifice plate has a vertical dimension PV1, PV1 is smaller than the vertical dimension OV1 of the image on the first group of frames, and the hole The plate second hole has a vertical dimension PV2, PV2 is smaller than the vertical dimension OV1 of the image on the second set of frames, so that the PV1-OV1 and PV2-OV2 ratios are in the forward and reverse directions, the tooth bottom and the film hole of the intermediate sprocket Large dimensional differences between vertical heights. 5. The film projection system of claim 4, wherein said first and second apertures have predetermined horizontal dimensions relative to their vertical dimensions to form a desired aspect ratio on projected images . 6. The film projection system according to claim 1, characterized in that, the device for moving the projection head and the film transmission mechanism receive the first position of moving the projection head to the first position and selectively running in the forward direction. a control input, and a second control input for moving said projection head to a second position and optionally in said reverse direction, said system further comprising: a lampshade baffle; an absolute video frame counter; A projection controller, used for the control of the projection head, the film transmission mechanism and the baffle, the controller receives the number of frames from the frame counter, opens the light baffle at the predetermined frame number in the forward direction, and opens the light baffle in the forward direction The light baffle is closed at the second predetermined frame number, the light baffle is opened at the third predetermined frame number in the reverse direction, and the light baffle is closed at the fourth predetermined frame number in the reverse direction. 7. The movie projection system of claim 6, wherein said controller includes means for forming said first control input in response to an external signal, and means for removing said first control input in response to a third external signal , and means for forming said second control input in response to a timer started by said third external signal. 8. The movie projection system according to claim 6 further comprising: the first and second film discs; first and second controllable motors driving said film reel; and It is characterized in that the first control input drives the controllable motor in the forward direction, and the second control input drives the controllable motor in the reverse direction. 9. The movie projection system according to claim 10, wherein the controllable motor is a servo drive torque motor. 10. The film projection system according to claim 1, wherein the projection head is mounted on a projection base, movable from the first position to the second position, and the projection base is mounted on a rigid light base removable, the system also includes: a first film path guide roller, mounted to the projection base, having an axis of rotation substantially perpendicular to the axis of movement of the projection base from the first position to the second position; a second film path guide roller, mounted to the lamp base, having an axis of rotation substantially perpendicular to the axis of motion of the projection base; the second film path guide roller receives film from a film reel, The film for projection is conveyed by the first guide roller to the projection head by the first guide roller. 11. The movie projection system according to claim 12 further comprising: a third film path guide roller mounted to said projection base with its axis of rotation substantially perpendicular to said direction of motion of said projection base, and a fourth film path guide roller mounted to said lamp base whose The axis of rotation is substantially perpendicular to the axis of motion of the projection base, and the third guide roller receives the film from the projection head and conveys it to the fourth guide roller, which in turn transfers the film Serve onto the second pan. 12. A film projection system as claimed in claim 12 installed in a self-contained operating cabinet surrounded by filtered intake air. 13. A movie projection system comprising: A film consisting of a framed first set of images spaced from the first side of the film, the set of images projected through the film in forward motion sequence; and a framed set spaced from the second side of the film a second set of images, the set of images being projected sequentially through the reverse motion of the film, the frames of said second set being substantially horizontally adjacent to the frames of the first set; a lampshade arranged to focus projected light on the perforated window; a lens arranged to project an image from the aperture onto a screen; A projection head, movable from the first position to the second position, and has a reversible film drive mechanism for receiving film and selectively moving film in the forward direction when said projection head is in the first position, and for receiving film and selectively moving film in the reverse direction when said projection head is in the second position move the video around, an aperture plate having a first aperture aligned with a first set of film frames and a second aperture aligned with a second set of film frames, in a first position of the projection head, the aperture plate A first aperture of the aperture plate is aligned with the aperture window, a second aperture of the aperture plate is aligned with the aperture window in the second position of the projection head, and means for moving said projection head from a first position to a second position, wherein the means for moving the projection head and the film drive mechanism receive a first control input to move the projection head to a first position and optionally in the forward direction, and move the projection head to a second position and optionally in the forward direction a second control input for reverse operation, the system further comprising: a light shield; an absolute video frame counter; A projection controller, used for the control of the projection head, the film transmission mechanism and the light barrier, the controller receives the number of frames from the frame counter, opens the light barrier at a predetermined number of frames in the forward direction, and opens the light barrier at a predetermined number of frames in the forward direction. Close the light barrier at the second predetermined frame number, open the light barrier at the third predetermined frame number in the reverse direction, close the light barrier at the fourth predetermined frame number in the reverse direction, The controller includes means for forming said first control input in response to an external signal, and means for removing said first control input in response to a fifth predetermined number of frames. 14. The movie projection system of claim 13, wherein said controller includes means for forming said second control input in response to a timer being started by said fifth predetermined number of frames. 15. The film projection system of claim 13, wherein said controller includes means for forming said second control input in response to a second external signal. 16. A film projection system comprising: Film consisting of a framed first set of images spaced from a first side of the film, the set of images being projected through the film in a forward motion sequence; and a framed set spaced from the other opposite side of the film a second set of images, the set of images being projected sequentially through the reverse motion of the film, the frames of the second set being substantially horizontally adjacent to the frames of the first set; a lampshade arranged to focus projected light on the perforated window; a lens arranged to project an image from the aperture onto a screen; A projection head, movable from the first position to the second position, and has a reversible film drive mechanism for receiving film and selectively moving film in the forward direction when said projection head is in the first position, and for receiving film and selectively moving film in the reverse direction when said projection head is in the second position move the video around, an aperture plate having a first aperture aligned with a first set of film frames and a second aperture aligned with a second set of film frames, in a first position of the projection head, the first an aperture is aligned with said aperture window, said second aperture is aligned with said aperture window in a second position of said projection head, and means for moving said projection head from a first position to a second position, wherein the means for moving the projection head and the film drive mechanism receive a first control input to move the projection head to a first position and optionally in the forward direction, and move the projection head to a second position and optionally in the forward direction a second control input for reverse operation, the system further comprising: a light shield; an absolute video frame counter; A projection controller, used for the control of the projection head, the film transmission mechanism and the light barrier, the controller receives the number of frames from the frame counter, opens the light barrier at a predetermined number of frames in the forward direction, and opens the light barrier at a predetermined number of frames in the forward direction. Close the light barrier at the second predetermined frame number, open the light barrier at the third predetermined frame number in the reverse direction, close the light barrier at the fourth predetermined frame number in the reverse direction, said controller comprising means for forming said first control input in response to an external signal, means for removing said first control input in response to a fifth predetermined number of frames, and means for forming said first control input in response to an external signal, and means for removing said first control input in response to a third external signal, and means for forming said second control input in response to a timer started by said third external signal.

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