EP0098874A1 - Improvement of motion picture image quality - Google Patents

Abstract

Cinematographic film is photographed with standard spherical lenses, with a total exposure of 35 mm aperture in the camera, giving in the ratio of 1.66: 1 an effective negative image area 75% larger than that of the format standard, 1.85: 1 of the large flat screen. The image on the frosted glass is centered on the center line of the film. The negative is optically printed on final anamorphic film using the standard side compression ratio, 2: 1, thus avoiding problems caused by projection on the large flat screen, such as blurred and grainy images, lack of depth of field unpredictable focus and framing. In the preferred embodiment of the invention, the aspect ratio used will be 1.66: 1. The center line of the film has an image offset from the standard center line of the "Academy", the height of the image framed on the frosted glass being printed according to the height of the anamorphic image, the unused parts of the top and sides being printed with an opaque border. Such an impression can be made from 35 mm photographic film, with the image on the frosted glass framed along the median line of the "Academy"; from 16 mm film photographed in the "super-16" format; or from high definition video tapes.

Description

SPECIFICATION

Improvement of Motion Picture Image Quality

Cross-References to Related Applications: This application is a continuation-in-part application of parent application S.N. 339,664 filed January 15, 1982, in the Patent and Trademark Office.

Background of the Invention:

The improvement of motion picture image quality of this invention is classified in Class 352, subclasses 44, 69, and 239; Class 355, subclass 52, and the like.

M. Lente, in U.S. Patent 3,865,738 issued February 11, 1975, discloses a motion picture film having pictures whose frame lengths are three perforation-pitch lengths. The print films may be prepared such that the prints may also be four perforation-pitch lengths. The images may also have an anamorphic horizontal reduction in the range of 1.5:1 to 1.25:1.

G. Monteleoni et al, in U.S. Patent 3,396,021, issued August 6, 1968, discloses an anamorphic wide-screen motion picture print made by exposing a negative in a camera without vertical or horizontal distortion, in a frame area of one-half normal height. A positive print is made by enlarging the vertical dimension of the picture in inverse proportion to the reduction of the negative feed rate Without "substantial change in width from that of the negative, producing a print of normal frame dimensions with an anamorphic wide scene filling the picture area of the print. In U.S. Patent 3,046,832 issued July 31, 1961, W. Winzenburg increases the luminous flux obtainable from projection equipment by providing a print of greater than standard frame size on standard film.

The present invention relates to a method of photographing motion pictures with attention paid to problems of the flat wide-screen system and to solutions offered by fullaperture photography and standard anamorphic projection.

The aspect ratio of a frame of 35mm film, as established by Edison and Lumiere at the end of the last century, is exactly 1.33:1, and this was the image used during the 25-year reign of silent films.

This standardization was challenged by the introduction of optical sound tracks at the beginning of the sound era. All of a sudden, three projection apertures were in wide use: The old silent aperture, for sound-on-disc release; the "Movietone" aperture, which simply reduced the width of the silent aperture to leave room for the sound track, resulting in awkward, almost-square image; and the "proportional" aperture, which reduced the height as well as the width to give the same 1.33:1 aspect ratio as that of silent films. Because of the uncertainty as to how a film would be projected, there was much compromise involved in the placement of lights and microphone booms.

Order was not to be had until the codification, in the early 1930 s, of the "Academy" aperture, whose aspect ratio was 1.38:1 (colloquially referred to as 1.33). For the next 20 years, cinematographers and directors never had to worry about how their films would be projected.

Although there was much discussion at the beginning of the sound era regarding the feasibility of wide screens, it is generally agreed that it took competition from a free 1.33 — television — to force motion picture studios into expanding the original 1.33 frame.

Since the introductions of Cinerama and Cinemascope in the early 1950 s, almost every conceivable combination of large negatives (VistaVision and 65mm photography), small negatives (Techniscope and Superscope), and anamorphic photography (Technirama and Ultra Panavision) has been used to increase the aspect ratio of motion pictures.

Besides the original Cinemascope anamorphic system, the only other surviving wide-screen format used in principal motion picture photography today is the "flat" (i.e., non anamorphic) wide-screen system, which was adopted only for its ability to produce wide images from standard 35mm cameras, lenses, and contact-printing techniques. In the United States, films are composed for an aspect ratio of 1.85:1 taken from the center of the standard 1.38:1 Academy frame, and projected with a short-focal-length lens and a 1.85:1 aperture plate. The flat wide-screen format uses only 63% of the standard anamorphic frame, while wasting 36% more negative and print stock.

A comparison to the 1.38 Academy format reveals the following projection problems of the 1.85:1 flat wide-screen system:

1. Apparent grain increase, due to the 26%-smaller image being projected onto a 35%-larger screen. Increased with the grain is the visibility of dirt and scratches.

2. Dimmer picture, for the same reasons, requiring the use of high-speed lenses in projection.

3. More critical focusing, due to the shallow depth of focus of high-speed, short-focal-length lenses.

It has long been observed that the lack of sharpness of flat wide-screen images is due primarily to the small image area of the negative. Because of the effects of negative emulsion grain, the full, potential of fine-grain positive stocks can be realized only with optical reduction from a larger negative.

The best-known example of this approach is Paramount's VistaVision process, whose large negatives were used almost exclusively for print-down to flat wide-screen prints. It was also common practice to shoot, with the full aperture, films to be printed in the Technicolor imbibition process, reducing to the Academy frame when printing the dye-transfer matrices. Even though the negative was only 27% larger than its print, there was claimed a noticeable gain in definition and decrease in grain. It is evident that the flat wide-screen system leaves much to be desired in the way of image quality. In addition, what is finally viewed by the public is often misframed. The classic example of this is the theater which shows all films at a 2:1 ratio, thus cropping and blowing up the already-small 1.85 frame, while reducing the width of anamorphic films. This compromise ratio damages the composition of 1.85 films more, as crucial headroom is severely tightened. Not only is headroom compromised in 2:1 projection of a 1.85 film, but the focusing, grain, and illumination problems are also magnified.

Moreover, there are problems in the exchange of films between the United States and Europe, since the U.S. uses the 1.85:1 ratio, while Europe uses 1.66:1. Similarly, any American director wishing to shoot in a ratio taller than 1.85:1, i.e., 1.75, 1.66 or the old 1.38, has almost no chance of having the film projected properly on a predictable basis. Directors and cinematographers must accept the fact that their flat wide-screen films are composed in the aperture plates of the theaters, and not on the ground glasses of their cameras. They can only determine what will be on the center of the frame on the print.

All of the above-mentioned problems are minimized in the standard anamorphic system employing complementary lenses with a 2:1 lateral compression ratio in photography and in projection. While anamorphic films are rarely shown at their complete 2.40:1 width, crucial height is almost always correct, as there is very little margin for framing error. This is because the frameline on an anamorphic print will be visible before headroom is misframed to a bothersome degree. Additionally, none of the illumination, grain, and focus problems encountered in flat wide-screen projection have to be considered: a larger image presents more light to longer lenses.

Yet, despite these projection benefits, fewer than 10% of American feature films are photographed with anamorphic lenses. A major complaint with the anamorphic format is that the 2.40:1 aspect ratio is too wide, is difficult to compose for, and requires scanning for television release. The other common complaint regarding anamorphic photography concerns the use of long focal lengths for the standard desired photographic angles of view. This results in decreased depth of field unless light levels are increased to allow the scene to be photographed at a smaller f-stop.

Thus, it is evident that the most desirable wide-screen format would have to combine the standard lenses and not-sowide frame of the flat system with the image quality and projection benefits of the anamorphic format.

SUMMARY OF THE INVENTION

Motion picture film is photographed with standard spherical lenses, exposing in the camera the full 35mm aperture, giving in the 1.66:1 ratio a negative image area effectively 75% larger than that of the standard 1.85:1 flat wide-screen format. The cut negative will be optically printed onto standard anamorphic release prints, bypassing the problems of flat wide-screen projection, such as dim and grainy images, shallow depth of focus, and unpredictable framing. The preferred embodiment employs the 1.66:1 aspect ratio. The 2.20:1 aspect ratio can also be produced according to the present invention.

This process invention solves problems created and implied by the flat wide-screen system. The solution must employ standard equipment in both photography and projection. This invention proposes that motion pictures not employing anamorphic lenses in photography use the full 35mm aperture, with the frame on the ground glass centered on the film centerline. The width of the projectable image would be 0.980 inch, with heights of 0.590 inch and 0.445 inch for the 1.66:1 and 2.20:1 radios, respectively.

The cut camera negative is optically printed to an anamorphic print, with the centerline offset 0.0495 inch to the Academy sound standard. The dimensions of the printing aperture would be identical to those of projectable image area framed on the ground glass, with the height of the projectable image on the negative printed to the standard 0.700 inch height of the anamorphic frame. Area not used on the top and on the sides of the image is printed with an opaque hard matte.

Included in the objects of this invention are:

To provide improved image structure, due to a larger negative image area.

To provide a means of bypassing the problems of flat widescreen projection.

To provide greater depth of focus during projection.

To eliminate unpredictable framing in theaters.

Other objects and advantages of this invention are taught in the following description and claims. BRIEF DESCRIPTION OF THE DRAWINGS

The description of this invention is to be read in conjunction with the following drawings:

FIGURE 1 illustrates the plan view of the camera aperture and the projectable image area used in the 1.85:1 flat wide-screen system.

FIGURE 2 illustrates the plan view of the camera aperture and the projectable image area used in the standard 2.40:1 anamorphic format.

FIGURE 3 illustrates the plan view of the projectable image area of a negative used in the present invention for films in the 1.66:1 aspect ratio.

FIGURE 4 illustrates the plan view of the projectable image area of an anamorphic print of the negative illustrated in FIGURE 3.

FIGURE 5 illustrates the plan view of the projectable image area of a Super-16mm negative.

GLOSSARY

FIGURES 1, 2, 3, 4, 5

1, 1', 1", 1''', 1'''' film

2, 2', 2", 2' ' ', 2"" - picture image

3 , 3 ' , 3 " - sound track

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

The present inventive advance in the process art proposes that motion picture films be photographed with spherical lenses, exposing in the camera the full 35mm aperture, with the frame on the ground glass centered on the film centerline. The cut negative is optically printed onto standard anamorphic prints, with the printing aperture having the same dimensions as the frame printed to the full height (0.700 inch) of the standard anamorphic frame, with unused information on the top and on the sides of the projectable image printed with an opaque hard matte. The preferred embodiment will use the 1.66:1 aspect ratio. Release prints are to be projected with standard anamorphic lenses.

The various comparative picture image sizes are listed in Table I on the next page, representing 35mm motion picture film.

This invention, in the preferred embodiment using the 1.66:1 aspect ratio, increases by 57% the negative image area, compared to that of the standard 1.85:1 flat wide-screen format (Table I, Column 1, line D and Column 2, line C). If one considers the larger screen area that a 1.85:1 image has to fill, compared to the present invention's 1.66:1 frame (for a given screen height), then the effective negative image area increase would be 75%. And, because the negative would be 42% larger than, and would be reduced to, its anamorphic print, highest-quality release prints would be obtained, as noted earlier. In addition, the effective print area increase (Table I, Column 2, line C; Column 3, line D) would be 23%. The result of the above negative and positive image area increases would be a substantial reduction of apparent grain and a significant increase in sharpness and definition.

In prior art illustrated in FIG. 1, value a is the correct height of a flat wide-screen print in the 1.85:1 ratio. Value b is the area exposed on the negative. The small image area and the wide margin for framing error inherent in said system is illustrated. FIG. 2 illustrates a standard print made from a negative photographed with an anamorphic lens. It is noted that the projectable area used on the print, value a, comprises almost the total area exposed on the negative, indicated by value b. Thus the small margin for framing error in the standard anamorphic format is indicated. FIGS. 3-5 inclusive serve to illustrate the procedures which the present invention discloses, overcoming the problems in prior art.

In FIG. 3, the projectable image area for the 1.66:1 ratio is indicated for negative material in the present invention. The total area exposed on the negative would be greater than the projectable image area, in accordance with standard practice. The specific area exposed on the negative is not indicated in FIG. 3 because the projectable image area framed on the ground glass would be the only area printed since its dimensions would match those of the printing aperture; thus the release prints will contain only the information framed by the camera operator. FIG. 4 illustrates how the correct height of the frame in FIG. 3 value a, is transferred to the correct height, value a, of the anamorphic format. It is unlikely that an anamorphic print will be misframed, since any error in projection will result in the frameline being visible.

Focus tolerances would be improved, because of the greater depth of focus offered by anamorphic projection lenses, which, for a given screen height, are 1-1/4 inch longer than those used in 1.85:1 flat projection. The increase in depth of focus will minimize not only focus drift through a reel but also the bad effects of film movement in the aperture. In addition, the fact that 1.66:1 anamorphic prints use the center 69% of the width of the standard anamorphic projection lens means that edge-to-edge sharpness will be improved.

Focus will also be aided because the almost-square image on prints in the present invention would be heated more evenly and would have less of a hot-spot problem. The larger print area for the smaller screen will help improve the illumination and will decrease the visibility of dirt and scratches. And, because of the increase in projection aperture height, problems with shifting framelines, due to printer misalignment, and with registration, because of a faulty intermittent mechanism, would be reduced 57%.

To many people in the motion-picture industry, the 1.85:1 flat wide-screen system's main fault is its wasting of 36% of purchased print stock. By contrast, the anamorphic format uses 0.700 inch of the 0.748 inch height of a 35mm frame, while the 1.85:1 flat wide-screen format uses only 0.446 inch. Thus, $540 of the $1,500 spent for a release print in the 1.85:1 format is not seen on the screen.

It is proposed to apply the present invention to the 2.20:1 aspect ratio, to offer an option to directors who wish to use a frame wider than 1.66:1, but would prefer not to use long focallength anamorphic lenses. Inasmuch as very few theaters project the full 2.40:1 ratio for anamorphic films, and instead crop the sides to varying degrees, with 2:1 representing the average worst-case, the 2.20:1 ratio can be considered the realistic maximum width. Additionally, this ratio would simplify blow-up to 70mm, since 2.20:1 is the aspect ratio of 70mm projection apertures.

In an embodiment of the present invention, films photographed in the standard flat system, using the Academy centerline, illustrated in FIG. 1, could be transferred to anamorphic print as described for the present invention. This application would receive all of the benefits claimed for the present invention with the exception, of course, of increased negative image area

In a similar embodiment of the present invention, prints from original material photographed in the format known as "Super-16", as illustrated in FIG. 5, could be made according to the specifications of the present invention. As a result, the complete 1.66:1 ratio of the original material will be seen on the screen, compared to the cropping of the image which results when flat 35mm wide-screen prints from Super-16 negatives are projected with a 1.85:1 aperture plate. As indicated in Table I, there is no increase in magnification needed for prints in the present invention (Column 3, line D), compared to standard flat wide-screen prints (Column 2, line D).

In a further embodiment of the present invention, material photographed on an electronic medium, e.g., high-definition videotape, can be transferred to anamorphic prints as described in the present invention.

Photographing a motion picture in the 1.85:1 wide-screen system while simultaneously taking into consideration framing for future television release has historically involved many compromises. If it is intended to exhibit a contact print from the negative on television, it is common to keep microphones and lights outside of the complete Academy aperture, which is illustrated as value b in FIG. 1. This procedure results not only in "loose" composition on television, since the image was framed for correct 1.85:1 headroom, illustrated by value a, but also in handicaps placed on sound and lighting personnel, as they are unable to get close to the actors for fear of having microphones and lights visible on television, not to mention in misframed projection in many theaters. Overcoming another limitation of prior art, in a further embodiment of the present invention, motion pictures photographed in the preferred embodiment could be transferred to videotape or 1.33:1 television film prints, deriving the 1.33:1 aspect ratio in both cases from the center of the 1.66:1 projectable image area, as indicated by value b in FIG. 3.

Thus, said films would have the correct frame height, FIG. 3, value a, in both 1.66:1 theatrical prints and in 1.33:1 television release. This embodiment will facilitate both the exhibition of television motion pictures theatrically, and the exhibition of theatrical motion pictures on television, including release on videotape and videodisc, and network and cable broadcast.

Furthermore, the 1.33:1 area extracted from the negative of the preferred embodiment (Table I, Column 1, line E) will have an image area 21% larger than that of the standard television "safe action" area (Table I, Column 2, line E).

In a still further embodiment of the present invention, a negative photographed in the preferred embodiment could be used as original material for a motion picture which would be distributed in a wide-screen "high definition" video format.

It is understood that the present invention is primarily concerned with full-aperture 35mm negatives and anamorphic 35mm prints, and can be duplicated using any means, including, but not limited to, standard color reversal intermediate and interpositive/internegative film processes, proposed digital film printers, and the like.

Many modifications in the improvement of motion picture image quality can be made in the light of my teachings. It is understood that within the scope of the claims, the invention can be practiced otherwise than as described.

Claims

CLAIM:

1. A process for making motion pictures comprising the steps of: photographing a scene on 35mm film, the frame on the ground glass centered on the film centerline, said frame encompassing substantially the full area between film perforations; optically printing said frame onto an anamorphic print employing standard 2:1 lateral compression ratio, during which printing the centerline of the frame is offset to the standard Academy center line, with the printing aperture having the same dimensions as the frame on the ground glass, and with a height of the standard anamorphic frame; and printing the unused area outside of the resulting frame with an opaque border.

2. In the process set forth in Claim 1 wherein the original picture image is photographed on the Academy sound centerline and said picture image is transferred to 35mm anamorphic prints.

3. In the process set forth in Claim 1 wherein the original picture image is photographed in the 16mm or the Super 16mm format, and said picture image is transferred to 35mm anamorphic prints.

4. In the process set forth in Claim 1 wherein the original picture image is photographed onto an electronic medium, and said picture image is transferred to 35mm anamorphic prints.

5. In the process set forth in Claim 4 wherein the original picture image is photographed on a standard or high definition video format, and said picture image is transferred to 35mm anamorphic prints.

6. In the process set forth in Claim 1 wherein the original picture image is photographed on 35mm film with the frame on the ground glass centered on the film centerline, said picture image encompassing substantially the full area between film perforations, and the center portion of said frame is transferred to standard videotape or 1.33:1 film prints intended for television release.

7. In the process set forth in Claim 1 wherein the original picture image is photographed on 35mm film with the frame on the ground glass centered on the film centerline, said picture image en compassing substantially the full area between film perforations, and said picture image is transferred onto an electronic medium.

8. In the process set forth in Claim 7 wherein said picture image is transferred to a high-definition video format.