FIELD OF THE INVENTION

This invention relates to a method and apparatus for producing and displaying a motion picture to theatrical motion picture audiences.

BACKGROUND OF THE INVENTION

Throughout its history, the motion picture industry has developed new technologies to make motion pictures appear more realistic to audiences than had previously been possible. The advent of sound, color and 70mm film in the late 1920s added a dimension of realism, when com¬ pared to earlier films. The same can be said of develop¬ ments from the 1950s, such as Cinemascope (wide screen image achieved through anamorphic compression and expansion) , Todd-AO (70mm film photographed at 30 frames per second with six-channel audio) and Cinerama (three synchronized projectors operating at twenty-six frames per second, pro¬ jecting films photographed at that frame rate onto a deeply curved screen) . While each of these systems increased the sensory impact received by audience members, none of these systems were compatible with each other or with conventio¬ nal motion picture exhibition systems then in use.

The same is true of the current high-impact systems, IMAX (15-perforation 70mm film travelinσ in the horizontal direction) or SHOWSCAN (conventional five-perforation 70mm at sixty frames per second) . The large film frame of IMAX and the high speed of SHOWSCAN limit their use to a few special venues. Conversion of films recorded in these for- mats cannot be accomplished for use in conventional motion

picture theaters without loss of the audience impact gained through the use of the special format, since such conversion requires the use of the frame rate of 24 frames per second. At that speed, the presence of such artifacts as grain, flicker and a lack of smoothness in the interpo¬ lation of motion serve to remind the audience viewing the motion picture that it is, indeed, a motion picture. The "cinematic" look associated with projection at twenty-four or twenty-five frames per second appears palpably dif-ferent to a viewer than films photographed at double these frame rates, where the artifacts mentioned above are reduced to imperceptible levels.

In an attempt to convert films photographed at sixty frames per second to the "conventional" rate of twenty- our frames per second, Trumbull (U.S. Pat. No. 4,889,423 (1989)) discloses a method for superimposing the first two images of each group of five shot at sixty frames per second into a single 24 fps frame, varying the amount of exposure of the the two images as superimposed. The next 24 fps frame is likewise made up of the superimposed images of the fourth and fifth frames of the group of images photographed at 60 fps. Trumbull's conversion method does not work in prac¬ tice, since the superimposition of images on each 24 fps frame causes objectionable strobing and blurring of the images as seen by the viewer. Moreover, the omission of the third frame of each group of five frames shot at 60 fps in¬ terrupts the smooth interpolation of motion available at the higher speed, thereby causing another objectionable artifact. The invention disclosed here allows the presentation of motion picture films that deliver a more realistic image to the viewers of such films, in conventional motion picture theater venues, than is currently available to such viewers. It is a primary objective of this invention to allow the c mbi¬ ning of parts of a motion picture image that will cause the audience to perceive portions of the images they see as impar¬ ting a strong illusion of reality to the viewer and other

portions of the images as having the conventional "cinema¬ tic" look associated with the frame rates of twenty-four or twenty-five frames per second. The invention disclosed here allows the audience to perceive certain portions of the ima- ges they see as more realistic than other portions of such images, thereby adding a dimensionality to the film as viewed. It is a further objective of this invention to provide a means for delivering a high-impact presentation to motion picture audiences and withdrawing the high-impact feature when it is not needed or desired. It is also an objective of the invention to allow easy conversion from the format described into a conventional format for general release and distribution to exhibitors not equipped to show films made in the format described here, without causing objectionable artifacts as a result of the conversion process.

The difference between the "cinematic" look delivered at twenty-four frames per second (and, by implication at twenty-five frames per second, since that rate is only four per cent faster) and the look delivered at significantly higher frame rates was noted by Trumbull in U.S. Pat. No.

4,177,160 (1984) at col. 5, lines 44 to 58 (patent for SHOW¬ SCAN system) . Trumbull goes on to state that the impact to which he refers is not available with the IMAX format because of its use of the twenty-four frames per second frame rate (at col. 5, line 64 to col. 6, line 10).

The rate of thirty frames per second has been used to create a more highly realistic effect than that available at twenty-four or twenty-five frames per second. Two films, Around the World in Eighty Days and Oklahoma, were commer- cially released in the Todd/AO format for projection at thirty frames per second. Despite the enhanced realism objained, this frame rate was abandoned because of its incompatibility with conventional exhibition at twenty-four frames per second, thereby preventing wide distribution for films photographed at thirty frames per second. For general release and exhibi¬ tion, it was necessary to have a second camera record the same

scenes at twenty-four frames per second that the first camera recorded simultaneously at thirty frames per second. More recently, the inventor herein has disclosed a method for transitioning between two different frame rates; speci- fically twenty-four and thirty frames Der second (Weisger- ber, U.S. Pat. No. 5,096,286 (1992)). This transitioning method uses selective underexposure of certain film frames to give the audience the impression of flicker and other artifacts present at the twenty-four frames per second rate until the film speed had completed acceleration to thirty frames per second. At that time, a brighter light was switched on to increase the brightness of the image as seen by the audience. The process was reversed for the slowdown from thirty to twenty-four frames per second. Noteworthy in the earlier Weisgerber invention is the means for modulating between high-impact (at 30 fps) and "conventional" film experience (at 24 fps) . High-impact systems currently in use (such as IMAX and SHOWSCAN) are always "on" and cannot be withdrawn. Such continuous high- impact presentation, even when it not needed to advance the story line of the picture, can overload the viewers with visual input; thereby creating another unwanted artifact. It is the "cinematic look" of films photographed and shown at twenty-four or twenty-five frames per second that is central to the present invention. The differences noted by Trumbull (160) between 24-fps presentation and higher speed presentation are precisely the differences in level of the illusion of reality which viewers perceive and that the present invention seeks to modulate. Thus, scenes (or even specific shots) within a single motion picture can have either the conventional cinematic look or the high-impact effect, at the discretion of the director of the ^" picture. In another application, images delivering the high-impact effect can be composited onto the same film frame as images delivering the conventional cinematic look. With the method described here, selected components of a film image can appear more realistic

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to the audience than other image components that the viewers observe simultaneously. As films prepared accor¬ ding to the present invention are shown, audiences will per¬ ceive that certain components of the action in the motion picture appear more realistic than other components of the action; thereby approximating the real-life experience where some events have a greater impact on a viewer's perception than others.

BRIEF DESCRIPTION OF THE INVENTION

This invention concerns the compositing of images onto the frames of motion picture film. It is desired that cer¬ tain portions of such images appear to the audience viewinπ the film as delivering conventional cinematic experience, while other portions of such composite images appear to give the audience the illusion of realism as delivered by high speed projection, as used in SHOWSCAN (Trumbull 160).

In the preferred embodiment of the invention, film se- quences or portions of images are photographed at a "conven¬ tional" frame rate of twenty-four or twenty-five frames per second, while the "high-impact" film sequences or portions of images are photographed at a rate double the rate at which the "conventional" film sequences or portions of images are photographed; forty-eight or fifty frames per second.

Scenes or portions of images for which a conventional "cinematic" look is desired are photographed at twenty-four or twenty-five frames per second in the conventional manner. Scenes or portions of images for which a high-impact presen- tation is desired are photographed (or animated and copied through an optical printer or using computer compositing techniques) at forty-eight or fifty frames per second. All scenes are projected at the higher of the two frame rates used, forty-eight or fifty frames per second, whether or not high-impact presentation is desired for any particular scene. Sequences photographed at twenty-four or twenty-five frames

per second are double-frame printed for projection at forty-eight frames per second (for images photographed at twenty-four frames per second) or fifty frames per second (for images photographed at twenty-five frames per second) .

Conventional Geneva projectors can be used for this application, but the projector must be modified to advance the film twice as often as in conventional operation. This can be accomplished by means known in the art. - The projector motor can be modified to operate at double the conventional speed, so the film is advanced forty-eight or fifty times each second, rather than the conventional twenty-four or twenty-five. Alternatively, a dobble-pin cam can be used to advance the star wheel twice as often, resulting in film pulldown occurring twice as often than with conventional operation. Projectors featuring high¬ speed pulldown and stationary pins for highly accurate registration, such as the "Linear Loop" projector manufac¬ tured by the Pioneer Technology Corp. of Burbank, Califor- nia, U.S.A., are also suitable for showing films according to this invention. Whatever type of projector is used for the practice of this invention, it is essential that the projector be equipped with a double bladed shutter so that two flashes of light will be presented for each film frame. On projection, all films are projected at either forty- eight or fifty frames per second with a double bladed shut¬ ter, so viewers are presented with ninety-six or one hundred image impressions per second. For portions of images where the "cinematic" look associated with photography at twenty- four or twenty-five frames per second is desired, each image is printed onto two successive frames of film for projection. The perception for the viewer would be the same as for con¬ ventional cinematic images projected at twenty-four or twenty- five frames per second. Strobing, motion blur and other ar- tifarts associated with photography at twenty-four or twenty- five frames per second would be retained, since only twenty-

four or twenty-five fresh images would be presented to the viewers during each second.

This invention allows portions of a motion picture fea¬ ture film to be photographed at twenty-four or twenty-five frames per second and projected to maintain the appearance of a film photographed and projected at that speed, while other portions of the film are photographed and projected at forty-eight or fifty frames per second to deliver a more rea¬ listic look with a dimensionality that is not present at frame rates of twenty-four or twenty-five frames per second. Not only is this modulation of the intensity of the experience perceived by the viewers available between scenes of a motion picture; image components photographed (or animated) at both twenty-four or twenty-five frames per second and forty-eight or fifty frames per second can be composited together during a sequence. The audience would then perceive both high-impact, visually-dominating action and other action that retains a cinematic appearance.

BRIEF DESCRIPTION OF THE DRAWINGS

The first three drawing figures represent motion picture film strips containing picture information. The portions of the film strips containing nonpicture information, such as audio information and time codes, are not depicted.

Fig. 1 shows a strip of film photographed at twenty-four or twenty-five frames per second, depicting a blank background and a man in the foreground.

Fig. 2 shows a strip of film containing twice as many images as on the film in Fig. 1 and photographed at double the rate at which the images on the film strip in Fig. 1 were photographed, such images being animated dinosaurs.

Fig. 3 shows a strip of film printed for projection at forty-eight or fifty frames per second, showing a composite of the images contained on the film strips depicted at Figs. 1 and 2, with each image from Fig. 1 composited with two

successive images from Fig. 2, with the resulting compo¬ site images showing the man depicted in Fig. 1 appearing to interact with the dinosaurs depicted in Fig. 2.

Fig. 4 shows a block diagram of the system used in the preferred emobidment of the invention. Film images from a camera, optical printer or computer are recorded onto separate film strips at twenty-four or twenty-five frames per second and forty-eight or fifty frames per second, these image components are composited onto another film strip, and this film strip is projected at a rate of forty-eight or fifty frames per second (the rate at which the greater number of image components were photographed per second), with a light brightness of typicallv 10.6 footlamberts (conventional light level) or 16.5 footlamberts (high brightness level) .

DETAILED DESCRIPTION OF THE INVENTION

The invention described herein is a method for combi- ning two levels of visual impact simultaneously in a motion picture presentation. Certain image components are photo¬ graphed at twenty-four or twenty-five frames per second and impart to the viewers of the film the sort of experience typically associated with the "cinematic" look of conventio- nal motion picture exhibition; including such artifacts as strobing, motion blur and interpolation of motion that does not quite appear smooth. For the purpose of this invention, these cinematic artifacts are desirable for cinematic artis¬ try and essential to keep from overwhelming the viewers. By contract, other image components are photographed at forty- eight or fifty frames per second. Because of the lifelike appearance of motion and lack of artifacts associated with twenty-four or twenty-five frame per second presentation, these image components appear palpably more realistic when viewed; they lack the "cinematic" appearance of twenty-four or twenty-five frame per second projection and appear far

more realistic than the image components photoσraphed at twenty-four or twenty-five frames per second. These two sequences produced at different frame rates are composited togetner onto a single strip of film to produce an image that appears highly realistic in part and "cinematic" in the other.

The options of twenty-four or twenty-five frames per second for the lower frame rate used and forty-eight or fifty frames per second for the higher frame rate used al- lows the invention described to be used on a worldwide basis. With the expectation that AC synchronous motors will (or, at least, can) be used to power such equipment as projectors and optical printers, the use of the twenty-four frames per se¬ cond speed is compatible with cinema presentation in the United States and other countries where 60 Hz. AC power is used. The use of twenty-four and forty-eight frames per second in this invention also comports with the use of twenty- four frames per second as a frame rate for conventional cine¬ ma operations and film presentation. In countries where 50 Hz. AC power is used, the use of twenty-five frames per se¬ cond as the lower frame rate and fifty frames er second as the higher frame rate renders this invention compatible with the variety of AC power in common use.

While the preferred embodiment of this invention envisi- ons twenty-four or twenty-five frames per second as the lower frame rate and forty-eight or fifty frames per second as the higher frame rate, other combinations of frame rates are pos¬ sible. Sixteen and thirty-two, eighteen and thirty-six or twenty-six and fifty-two frames per second are feasible frame rate combinations for the invention described. The only re¬ quirement is that the lower frame rate be thirty frames per second or less, and the higher frame rate be more than thirty frames per second. This is because the artifacts thatdeliver the "cinematic" look at such frame rates as twenty-four or twenty-five frames per second begin to disappear at thirty frames ^p er second and disappear completely as the frame rate

rises to more than thirty frames per second. The combina-*- tion of thirty and sixty frames per second can be used in the practice of this invention, although the results will not be as perceptible as when the lower frame rate is twenty- four or twenty-five frames per second. In the preferred em¬ bodiment of the invention, therefore, the lower frame rate should be twenty-four or twenty-five frames per second and the higher frame rate should be forty-eight or fifty frames per second. To allow for the compositing of image components according to the invention, the higher frame rate should be double the lower frame rate.

The drawings provde an example of the practice of the preferred embodiment of the invention. There were sequences in the American film Jurassic Park where people (photographed running as live action) appeared to be chased by dinosaurs, which were computer-animated creations. In the actual post- production of Jurassic Park, the live-action images of the people running were composited with the computer-animated images of the dinosaurs, both at twenty-four frames per se- cond. For the present invention, let us assume that similar live-action images of a man running, photographed at twenty- four or twenty-five frames per second (Fig. 1) , are composi¬ ted with computer-animated dinosaurs (Fig. 2) , although the dinosaur images are produced so that forty-eight or fifty of them are presented to the audience each second (along with twenty-four or twenty-five images of the man running as the components of the scene) . Fig. 3 shows the composited images resulting from the mixing of the image components of Figs. 1 and 2. The images depicted in Fig. 3 will be projected to the audience at forty-eight or fifty frames per second, with each image component from Fig. 1 presented twice. What the viewers perceive is that the man in Fig. 1 appears "cinematic" and confined to the apparent plane of the screen, while the dinosaurs depicted in Fig. 2 will appear much more real. Their motion will appear much smoother than that of the man, and the dinosaurs will seem to be free from the confinement

of the apparent plane of the screen. Thus, the dinosaurs will appear able to "pop out" from the confines of the screen and jump toward the audience.

In converting from twenty-four or twenty-five to forty- eight or fifty frames per second, each image on Fig. 1 is printed twice, so image component 11 appears at composited images 31 and 31'; image component 12 is printed at compo¬ sited images 32 and 32' and image component 13 is printed at composited images 33 and 33*. Adding the image compo- nents from Fig. 2, image components 21 and 21' are mixed successively with image component- II to form composited images 31 and 31'. Similarly, image components 22 and 22' are mixed with image component 12 to form images 32 and 32' and image components 23 and 23' are mixed with image compo- nent 13 to form composited images 33 and 33'. This compo¬ siting treatment continues throughout the entire scene, as long as the filmmaker wishes to combine onto a single image both components that have the "cinematic" look of twenty- four or twenty-five frame per.second presentation and the "high-impact" look of forty-eight or fifty frame per second presentatio .

In the preferred embodiment of the invention, projec¬ tion of films should be accomplished by a projector featu¬ ring high-speed pulldown and highly accurate registration. Conventional Geneva projectors are suitable, if modified to advance the film twice as often as in conventional operation. This can be done through methods known in the art. The pro¬ jector motor can be modified to turn at double the conven¬ tional speed, thereby driving all operations twice as often. Alternatively, a double cam pin (rather than the conventio¬ nal single cam pin) can be used to move the star wheel twice as often as in conventional projection, thereby advancing the film twice as often. Alternatively, a more advanced ap¬ proach, such as that used in the "Linear Loop" projector manufactured by the Pioneer Technology Corp. of Burbank, Cali¬ fornia, U.S.A., can be used. Optimally, film pulldown should

be accomplished in three or four miliseconds to allow suf¬ ficient light to pass through the film to give the desired audience impact. A double bladed shutter is also essential. In the invention described here, the need for a special light source required in Trumbull 160 is eliminated, due to advances in commercial single-lamp light sources. The light efficiency of contemporary projectors, with up to 7000 watts available, allows sufficient light to produce the effects desired for the practice of this invention. The effects noted in Trumbull 160 are obtained with the present invent__on at forty-eight or fifty frames per second.

Moreover, the psychological effects 'Trumbull claimed to achieve are available with the invention described here without resort to a frame rate of sixty frames per second. The presentation of forty-eight or fifty images to the viewer each second leads to a comparable level of smooth¬ ness of motion to that available at sixtv frames per second. However, at recommended light levels (sixteen footlamberts or more) , flicker remains perceptible. Use of the double bladed shutter at forty-eight or fifty frames er second, however, eliminates flicker by presenting ninety-six or one hundred impressions per second to the viewers. Thus, the beneficial effects of the Trumbull system are obtained with¬ out the need for equipment that is limited in its applica*- tion to special veaues.

It is also feasible to modify the method described here to highlight the difference between the "high-impact" and "cinematic" images in separate scenes in a film. Weis- gerber 286 taught the use of brighter light for "high-impact" scenes than for scenes that are designed to retain the "cine¬ matic" look. In such instances, where it is desired that an entire scene be more visually impressive than other entire scenes, light level can be varied according to Weisgerber's previous invention. Similarly, Weisgerber also teaches the selective underexposure of certain film frames as printed to create the artifact of flicker when it is desired that the

viewers of the film perceive flicker during the speed change. In the above-described invention, the portions of images which the filmmaker wishes to present the "cinematic" look can be selectively underexposed to appear less bright than the high-impact components of the image, while the high- impact images will appear brighter and more realistic by comparison; an effect that also works for composited scenes. In the preferred embodiment of the invention, the film format used is 70mm film (65mm negative) with five perfora- tions per frame. With high-speed pulldown increasing the light that reaches the screen and pin-registration increa¬ sing the perceived resolution of the images projected onto the screen, it is possible to approach (or even exceed) the SMPTE standard of resolution of sixty line pairs per mili- meter. In any event, the resolution available with the method described can also accommodate any other standard or nonstandard film format or guage. The resolution available with 35mm film stock will be less than with 70mm film, but it will still be significantly higher than conventionally available with standard 35mm release prints, due to the use of pin-registered projection.

The increased amount of light reaching the screen due to high-speed pulldown projection, along with the increased resolution delivered by the pin-registered projection mecha- nism, allows a greater amount of magnification to be accom¬ plished than was previously feasible. It is, therefore, pos¬ sible to install larger screens in conventional motion pic¬ ture theaters than had heretofore been possible. The inven¬ tion described here facilitates a situation where all (or nearly all) of the audience members view a motion picture screen so large that the image will cover the entire "front" wall of the auditorium, from wall to wall and from floor to ceiling. Larger screens that can be used in accordance with this invention (as opposed to smaller screens necessitated by conventional methods and technology) can be masked through use of the methods taught by Vetter (U.S. Pat. No. 3,475,086

(1969)) (upper and side masks) and previously by Weisberber (U.S. Pat. No. 5,121,086 (1992) ) (lower screen mask) . With the use of these methods, the beneficial effects delivered by the invention described here are available with any stan- dard or nonstandard film format, quickly and automatically. The invention described here now allows the filmmaker to modulate the amount of impact that a component of an image will have upon the viewers of the film being presented; not only between scenes, but with simultaneous action within a single film sequence. While the method described here per¬ mits the compositing of high-impact" and "cinematic" images together, it is not necessary that such compositing always be done. The "high-impact" mode may be reserved for visually impressive scenes, where it is used to best advantage. For scenes where an impressive visual experience is unnecessary or could even be undesirable (such as a scene where the dia¬ logue between two characters advances the story line of the film and a conventional "cinematic" presentation keeps the viewers of the film fi-om being visually overloaded) , the "cinematic" look can be retained.

Using different film technologies to produce different levels of impact on the viewers is not new. As far back as the mid-1920s, color scenes were used selectively for the ballroom scene in The Phantom of the Opera (1925) and the Resurrection scene in King of Kings (1927) . The Wizard of Oz (1939) depicted events occurring in Kansas in black and white (with sepia tint) and the events occurring in the mythical land of Oz in full color; an effect achieved through scenic and costiime design, not be compositing two images. Until now, there was no method available for compositing high-impact image components with other image components that retain the "conventional" look of the standard techno¬ logy. The present invention also demonstrates the first use of different frame rates which are combined to advance a mo- tion picture story line in real-time mode. In the present invention, the action does not appear to speed up or slow

down, as conventional slow-motion and fast-motion photo¬ graphy deliver. Instead, the different frame rates combine to deliver either a greater or lesser illusion of reality to the viewers of the film. In addition, high-impact image components can be joined with lower-impact image components to create a "dimensional" effect upon the viewers of the pic¬ ture, thus adding another variable that can be modulated under the creative control of the filmmaker.

This creative control can be used in many different ways. Live action photographed at twenty-four or twenty-five frames per second can be composited with other live action photographed at forty-eight or fifty frames per second, so that people who will appear "cinematic" to the viewers will be watching other people involved in action that will look highly realistic and dimensional. Live action can also be composited with animation. Live action photographed at twen¬ ty-four or twenty-five frames per second will give the im¬ pression that real people have been dropped into a cartoon setting. This live action can be composited with animation printed for projection at forty-eight or fifty frames per second. Any style of animation can be used, from cartoon drawings to sophisticated computer-generated images. Ani¬ mation at twenty-four or twenty-five images per second can also be combined with animation at forty-eight or fifty ima- ges per second. In any application, the image components photographed or printed at forty-eight or fifty images per second deliver a dimensional effect not noticed at twenty- four or twenty-five images per second, since viewers per¬ ceive the screen itself as an artifact of projection at twen- ty-four or twenty-five frames per second. The images projec¬ ted at forty-eight or fifty frames per second will appear to escape the boundaries of the apparent plane of the screen.

The metod described is feasible for installation in any conventional motion picture theater, as opposed to such high- impact systems as IMAX and SHOWSCAN, whose lack of adaptabi¬ lity to the theatrical exhibition marketplace limits their

use to a few special venues and make them unsuitable for full-length feature films.

Conventional equipment is used in the invention des- scribed, except that the preferred projector should be a high-speed pulldown, pin-registered type equipped to show films at forty-eight or fifty frames per second, through a double-bladed shutter. This configuration delivers ninety- six or one hundred impressions per second to the viewers; two impressions .of each image photographed or printed at forty- eight or fifty frames per second and four impressions of each image photographed or printed at twenty-four or twenty-five frames per second. In practice, the showing of forty-eight or fifty frame-per-second images twice will produce the high- impact effects described in Trumbull 160; while the showing of the twenty-four or twenty-five frame-per-second images flashed four times (each image duplicated and then flashed twice) will retain the "cinematic" look associated with pro¬ jection at twenty-four or twenty-five frames per second.

The method described also provides other advantages not available with other high-impact systems, in addition to the ability to selectively blend high-impact and conventional "cinematic" images. If a filmmaker does not wish to mix high and lesser-impact images within a single film frame, it is still possible to intercut high and lesser-impact scenes within a single motion picture, without the necessity of specially treating certain frames of film to accomplish a transition between two different frame rates. Moreover, the method described allows easy conversion from the rate of forty-eight or fifty frames per second to the conventional rate of twenty-four or twenty-five frames per second for general release. Images photographed at forty-eight or fifty frames per second will be transferred by printing alternate frames to make prints for exhibition at a twenty-four or .twen¬ ty-five frames per second. The advantages of the dimensional high-impact scenes and images will be lost, but general release prints can be made without the difficulties encountered in

O 9

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converting (for example) from sixty to twenty-four frames per second, as described in Trumbull 423.

The method described is available for use with any film format, and transfer of images can be accomplished through an optical printer or by use of computerized image transfer processes known in the art. To enhance audience impact, the improved resolution available permits greater magnification and, therefore, a larger screen to be fitted to the archi¬ tecture of the auditorium than had heretofore been feasible. Any film format may be used in accordance with this in¬ vention, but 70mm film will deliver greater resolution than 35mm. In any event, the use of the invention described will greatly improve the visual dynamics of the dimensionality of the film upon the viewers of motion pictures, over that available with conventional 35mm release prints (with easy conversion to that format, when desired) .

No change is made in the physical film stock; only the frame rates are varied and selected to produce the desired effect. Audio and other nonpicture information can be re- corded onto the film to be shown in the usual ways known in the cinema art. Due to the high-impact nature of some ofthe images to be presented, however, it is expected that the sound system used will also present an appropriate degree of auditory impact. This invention expands the creative latitude available to the filmmaker. It is now possible to modulate audience perception of reality in an easy and relatively inexpensive manner, and to an extent not possible until now. The exam¬ ples described for applications of this method should be viewed as illustrative, and not limiting. Other prospec¬ tive applications and embodiments of this invention should be considered as lying within its scope.