GB2226646A - Stereo camera having separable carrier mounted film sections - Google Patents

Abstract

A stereo camera, has a film pack or cartridge 8, which may contain a plurality of ready-mounted 35 mm full frame stereo transparency film units 7. The cartridge is located and aligned within the camera so that each film frame and its corresponding mount of a stereo pair 6, may be concentric, or thereabout, with its respective lens 14, and shutter 13. The arrangement allows a particular lens separation distance to remain consistent with a pair of, if required, 36 x 24 mm film frames. The pair of mounts are releasably secured to a dividing segment and can be detached; each one is given a particular orientation prior to being located within a stereoscope for viewing. A first opening 3 in the camera is provided for locating and aligning the film pack 8. A second opening (24 Fig. 3) is provided for ejecting exposed film units. A flash facility (20 Fig. 3) may be provided. <IMAGE>

Description

IMPROVEMENtS I}s OR RELATING TO STEREOSCOPIC PSOTOGRkPAIC APPARATUS.

This invention relates to stereoscopic photographic apparatus.

The stereoscopic aspect of photography has evolved and been received from the beginning, albeit sporadically. When related to photography, a stereogram consists of a pair of two dimensional pictures, each one taken by a camera, usually from one of a pair of lenses separated by a distance, on a horizontal plane, of approximately 64 mm (the average separation distance of the eyes ofan adult person).

Each lens of a stereo camera captures an individual view of the same subject, emulating the result of what happens when each eye of a person receives its own light directly from a subject, enabling two slightly different images to be relayed to the brain that then fuses them together, to create one united picture view revealing improved depth and clarity of detail, compared to the impression received when viewing the actual subject with one eye only or when viewing a two dimensional picture.

Viewing a stereogram correctly installed within a stereoscope enables the eyes to effectively recapture the subject as originally viewed, now depicting an apparent three-dimensional reconstruction of that subject.

Superior depth and clarity of detail is revealed, compared to the impression captured on film by a single lens camera taking one single two dimensional picture.

Prior to the advent of 'I35' 35 mm film, stereograms had been produced using a variety of sensitive materials and camera types. Early photographic practice using stereoscopic means, adapted the existing plate cameras. Light sensitive glass plates that were usually exposed for single 2-D images, were divided into two separate side by side exposures.

However, due to the inherently large size of the plates, the lens separation of the camera was wider than the ideal 64 mm. Cameras that were specially designed for stereoscopic use emerged, still using emulsion coated glass plates that had evolved into suitably smaller units, as tne newer cameras were more compact. Sheet film was introduced as an alternative medium. Roll film adaptors were also introduced as an alternative camera fitment. The glass plates needed to be mounted into metal sheaths prior to installing into the camera, either individually in single holders or in bulk inside a magazine; they covered the back of the plate, preventing unwanted exposure of preceding units within the magazine; also embracing the two long edges of the plate.The sheet film strips were also mounted in a similar fashion. he loaded magazines made the overall weight of the camera considerable. The glass plates in particular could be awkward to manipulate into positive stereograuis ready for viewing.

After exposing and developing the plate or sheet film, it was necessary to hold them up to the light, emulsion side facing away. The images would then appear the right way up and right way round after inversion of the combined paired unit); but the left hand image would be on the right hand side and nica persia, the reason being that the images were upside down inside the camera. Inverting them brought the frames to the wrong side of the plate or sheet. As it was essential that each eye should view the picture made from its own corresponding view point, it was necessary to transpose the pictures.

To be able to transpose glass plate stereoscopic picture units, one needed to use special apparatus for cutting and transposing, in order to arrive at correctly positioned positive stereograms. The glass was vulnerable to breaking during this process. The resulting complete positive stereogram then needed to be mounted, ready for installing into a stereoscope for viewing. Alternatively, a glass plate negative or sheet film negative could be used intact, in order to produce correctly positioned stereoscopic positives using a transposing frame and exposure apparatus.

Dust getting between the positive element and the light source, often caused undesirable spots to appear on the final positive. Another alternative was to use an untransposed positive plate or sheet that could, after mounting, be located and viewed inside a special elaborate stereoscope containing transposing prisms. A more tedious method of transposition could be one where projection was used when enlargements were required. Either transparent negative or diapositive stereoscopic pairs could be produced and it became common practice to produce positive transparencies from negative material.Negative stereoscopic pairs on sheet film either needed to be cut apart, after de-mounting from its sheath, for transposing purposes to produce properly positioned prints or positive transparencies, or the positives on paper or sheet film had to be cut apart after development, then transposed and re-mounted.

Sheet film diapositive transparencies also needed to be de-mounted before being developed and cut apart, inverted and properly positioned within its stereogram mount ready for viewing. Alternatively they could be left intact after development and then, after mounting inserted into a transposing stereoscope. The metal sheath that held its stereoscopic photographic material nas necessary, in order to protect the emulsion of successive units within their magazine, as the sheaths rubbed over each other between individual exposures.

Accordingly it is desired to provide a stereoscopic transparency film unit that is compatible with the proposed 'I35' 35 mm film stereoscopic camera that can combine together, for exposure and development, two full sized 36 x 24 mm transparency positive films that are fully integrated within their mo nts; tnat after development can be conveniently inverted, separated from each other and transposed without any need for special apparatus in order to accomplish this and without any inherent tedious or delicate aspects to be accorded to this procedure; that may be reaay for viewing without the necessity for customery independent mounting of the film frames.

Stereograms now usually result from 'I35' sized 35 mm cassette roll film, exposed within a conventional stereoscopic camera, or with the aid of a device attached to the front of the lens of a conventional camera, enabling the pair of stereogram images to form side by side on one 36 x 24 mm film frame; a standard 45 / 50 mm lens is usually retained with the latter, that can produce good results, but witn less convenience and certainly less visual impact due to a relatively narrow angle of view with that particular lens focal length and also due to the small 18 s 24 mm picture size.

The popularity of 35 mm stereo cameras began around 1947. Since then there have been two types, in particular, that have been commercially successful. Each uses the same film type, but producing different film formats and therefore different lens separation distances have to be utilized. the first type produces pairs of 22 x 24 mm film frames. Here, the corresponding images on the exposed roll of film, are separated by two frames, necessitating a larger than ideal lens separation of 69.5 mm in order that there be sufficient space between the shutters in order to fit these two small interposed frames. The two intermediate frames are interposed between each stereo pair and the film roll ii wound a distance of two frames for each set of exposures, eventually resulting in a blank wasted frame at each end of the roll of film.With this format, although a large number of exposures can be obtained from one roll of film, only small pictures result, which limit the amount of vieual impact potential compared to that given with larger 35 mm film frame stereoscopic reconstructions.

The other popular 35 mm film stereo camera, utilized a film format size of 24 x 30 am frame size allowing the camera to retain a desirable lens separation distance of 64 mm or thereabout. Here we have a larger film frame giving improved visual stereoscopic impact when compared to the 22 x 24 mm film format but necessitating the use of an even more elaborate film transport system within the camera. 35 ii stereo cameras.

with their complex film transport systems, sometimes allow individual frames on an exposed roll of film, to overlap to a significant degree.

One intermediate 24 x 30 mm frame can be interposed between each stereoscopic pair of exposures. As a result, the film must be wound on alternately one frame and three frames; the finished film needs to be cut into units of two complete sets of stereoscopic exposures. The film transport knob on the camera usually needs to be geared to advance four frames per revolution. Two film locks need to be spaced one quarter revolution apart, then yield the necessary interval of one and three frames alternately.

Accordingly it is desired to provide a 35 mm film stereoscopic camera that does not need to use film in roll form and that does not therefore, need any kind of special compensatory lateral film transport mechanism in order to allow, primarily, relatively large film frame sizes to be correctly exposed in pairs. It is therefore desired to provide a 35 mm film stereo camera that is capable of exposing successive pairs of full sized film frames, whilst being capable of retaining an ideal lens separation distance of 64 mm or thereabout. It would therefore be desirable to provide such a camera whereby'the narrow space between lens shutters will not be an inhibiting factor in order to expose successive full sized film frames using 35 mm film, without wasting film.It is also desired that such a camera will not need to expose the kind of film that traditionally requires to be sorted and cut in order to select, locate and arrive at appropriate sets of mounted stereoscopic paired positives.

It is also desired to provide such a stereo camera that can utilize the largest film frame size, compatible with the popular '135' 35 mm film format that allows successive stereo pairs of film units (the two film sections located side by side, with each film face concentric, or thereabout, with its respective lens) to be exposed, so that each film frame will contain its complete respective image and retain its appropriate position, without there being any risk of adjacent frames overlapping.

A conventional camera may be utilized in order to take a stereo pair, by utilizing apparatus which will enable its single lens to take two sequential exposures, the camera being moved in a horizontal plane, more or less 64 mm between exposures. During this procedure, it is a common requirement to have both axis directions parallel. Consequently the left image captures more of the left side of the subject than of the right side and vica verca for the right image. Compensation in the mounting procedure is necessary, otherwise left and right eages will not be seen stereoscopically (floating edges). The mounting manipulation tnat avoids this, also causes some slight image loss.

To help overcome the aforementioned inconvenience, real stereo cameras (essentially a device consisting of two cameras in one box) have parallel lens axis that avoid image lose by usually having the film apertures 8o placed as to provide a 'built-in-window' which elliminstea image loses by using convergence. This means they are at a greater distance from each other than the lens separation. The film aperture separation and lens separation may typically be 7Ii mm and 69+ mm respectively.This relationship between the axial orf-set of the lenses and the film aperture separation, controls the horizontal image position in the mount allowing the formation of a correct window effect only if vertical and rotative position factors of the stereo pairs are accounted for also.

The borders of the picture areas are chosen in such a way that they form the aforementioned 'window' in the stereoscope, behind which the stereo scene unfolds itself. However, this 'automatic' camera setting, for a given 'window' position is only effective if the actual mounting procedure is correctly applied. Correct horizontal separation in the viewing mount ensure the foreground of the subject does not protrude through the stereo window. If this happens, the stereo pair will be positioned too close together. The aforementioned 'automatic' stereo system will allow the stereo window to be placed at a certain distance in the scene.

There are other automatic slide mounting camera systems that take into account vertical and rotative film mounting positions, as well as the horizontal one regarding the relative placement of the two viewed images in their mounts and therefore allow freedom from mounting errors through the three stages of photography, mounting and viewing. For example, a special stereo camera exists that takes stereo pairs of full frame image size on 35 mm film with a lens separation distance that is significantly largerthanaverage(74.7 mm) therefore allowing room for a second frame to be interlaced between each stereo pair on a roll of film that also necessitates an uneven winding of alternately-one and three frames. It has precise optical alignment for register pin mounting on a single 35 mm film.The use of register pin mounts, restores correct alignment of the twin transparencies. Its film transportation is required to position the film so that the film perforations are reasonably close to the correct symmetrical position, relative to the exposed frames, or the edge of the image will come into view within the clear area of the mount.

After development of the film, the stereo pairs need to be located, cut from a roll and then transposed prior to mounting. Thie system necessitates a camera configuration that is relatively bulky, in part due to the larger than usual lens separation distance, in order to allow an unrelated interposed frame between each exposed pair.

Another automatic system using 35 mm roll film, avoids exposing an unrelated frame between stereo pairs, thus negating one reason for cutting the frames apart and avoiding accuracy in mounting problems, the alignment of the images being identical for every pair and defined by the camera.

However, because the film ie not intended to be cut in between each section of a pair for transposition of the images, this system is not compatible with conventional stereoscopes and projectors. The combined pairs are, however, separated from each other for editing purposes, prior to viewing in a special projector or special transFosing stereoscope, and rejoined so that the frame pairs are joined on one continuous strip of film instead of using mounts. Re-editing a sequence can, however, be complicated e.g., removing one picture involves undoing three splices and making two. The relevant camera uses a 66 a lens separation distance, so there is a significant amount of wasted unexposed film in between the sections of each pair of exposed frames.Only twelve pairs are obtainable on a standard 36-exposure roll, due to the significant amount of unexposed lost film between pairs. The related camera is a one-off example formed from two existing. conventional cameras, combined and integrated together; one inverted in relation to the other in order that a reasonable inter-lens separation distance may be obtained. The resulting configuration dictates the two shutter blinds travel in opposite directions, therefore precise synchronization may only be secured in the middle of the picture, this being a disadvantage when taking fast moving subjects.

Accordingly it is desired to provide a stereo film system that, when used in conjunction with its companion stereo camera, will automatically enable stereo pairs to be accurately registered in relation to each other and each to their respective integrated mount half of their combined carrier, thus maintaining correct horizontal and vertical alignment and freedom from rotative error through the three stages of photography, mounting and viewing and thus provide a ready-mounted stereo pair, incorporating an already defined film/mount relationship that will provide the observer with a correctly positioned stereo window effect within a conventional viewing system. It is also desired to provide the means whereby traditional cutting of stereo pairs from a roll of film and subsequent transposing and mounting procedure and potential film wastage may be elliminated.It is also desired to provide the means whereby such full frame 24 x 36 mm, or thereabout, stereo pairs may be exposed within a real stereo camera, utilizing either more or less the standard 64 mm lens separation distance, preferably between 55 mm and 75 mm. It is also desired to provide a film and related camera system that is lhserently compact and convenient to use. It is also desired to provide a stereo film and camera system that provides the means to ensure each successive exposed stereo pair will retain their full image area thus elliminating potential film overlap problems generally associated with real stereo cameras and their particular type of film transport mechanisms.

Since the advent of modern colour diapositive film, this has been the most successful and popular film medium for the stereoscopic aspect of photography in particular. It would be desirable therefore to be able to incorporate, as an optional medium, an integral immediate developing colour transparency film, within the proposed 35 mm film stereo camera concept, where its convenience factor can be used to advantage; whereby the superior amount of detail that it is possible to see whilst viewing a stereoscopic reconstruction of a subject, when compared to a conventional 2-D picture would be made available, on a pair of full sized 36 x 24 mm film frames exposed via lenses separated by the ideal, if required, 64 mm distance, or thereabout, within a span of just a few minutes between exposure and final location of the stereogram within a stereoscope.

Accordingly it is desired to provide a 35 mm immediate developing colour diapositive film medium option that can be integrated within the readymounted stereo transparency film unit. After exposure within tne camera, each successive stereo film unit that contains an immediate developing integral structure type of diapositive film, will begin its developing process as it passes between eject roller. Such a film unit may contain colour dyes, having similar transparent qualities to that of conventional colour diapositive film, that can be persuaded to migrate from negative layers, across to a positive receiving side, within the unit structure, in order to achieve a desired positive image. Each preceding film unit within its pack may be protected from unwanted light, as with conventional diapositive film during exposure of the primary unit.It is also desired to provide such a diapositive film medium with an inherent capability to protect its developed image within its enclosed structure from general abuse. The film medium will achieve this form of image protection via an integrated transparent plastic member, similar to that used with existing integral immediate developing print film.

According to the present invention, there is provided a film and related stereo camera arrangement in which two transparency film sections are mounted on a carrier, the film sections being spaced apart to permit ready separation, one from the other, after picture development. A first opening in the camera is provided for locating the carrier unit within its cartridge and means provided for exposing successive combined pairs of such ready-nounted film units and a second opening is provided for ejection of the exposed film units which may contain, if required, a particular full frame film format that is commensurate with a particular lens separation distance that may be, if required, equal to the average interpupiliary distance of an adult person. The combined slide unit may remain intact, after development, and therefore will relate to a particular alternative viewing procedure.

, As matters of convenience and by way of example, the stereoscopic photographic apparatus may embody or be constructed with the following: (a) The carrier may be provided with alternative separation means other than a perforated line or lines.

(b) The film cartridge may contain more than one film unit, to be positioned one behind another.

(c) The camera and carrier unit may be adapted to utilize optional sizes of mount and or film frame pairs.

(d) Preceding film units within their cartridge, may be protected from unwanted light during exposure of the primary film unit by opaque means.

(e) Information may be provided on the carrier, indicating to the operator a procedure for correctly orientating each detached film mount section, after development, for correct viewing.

(f) The camera may be adapted to incorporate a lens separation distance either more or less than standard, preferably between 55-75 mm, or thereabout.

(g) The camera may be adapted in order to provide the means to locbte and utilize optional film mediums.

(h) The camera may be adapted to provide ejection rollers of a particular alternative form when used in conjunction with conventional diapositive film sections, in order not to adversely affect the film emulsion during ejection.

(i) The camera may be adapted in order to provide optional types of film cartridge arrangements.

(j) The internal camera configuration may be arranged to provide a relieved aspect, providing a clearance on the appropriate parts of the film cartridge and camera mount arrangement, in order to prevent the film emulsion from being adversely affected during ejection.

(k) The camera may be adapted to provide the means to locate individual film sections that are ready-mounted and arranged side by side, separated from each other, within a common cartridge or, instead, two separate cartridges located side by side, each one containing its own readymounted film section.

(1) The camera may be adapted in order to provide the means to locate a sheet film holding device, enabling each sheet of a related film medium to be loaded and exposed, one at a time.

(m) The camera may be adapted in order to provide the means to locate and utilize an integral immediate developing transparency film medium and such a medium may be adapted to be incorporated into the proposed stereo Carrier unit that may include an integrated colour development facility.

(n) The film carrier may be fabricated from any one, or a combination of any of a variety of materials, such as for example, paper, card and or plastic.

(o) The camera ejection system may be adapted to either provide an electronic motor drive or a manual hand crank or similar actuation.

(p) The camera may be adapted in order to provide an alternative ejection means, other than a roller form, where conventional diapositive film is utilized.

(q) The camera may be adapted to provide an external attachment means for a box or magazine, in order to contain, when required, ejected exposed film units from said camera.

(r) The film sections and associated carrier unit may be retained intact as a combined stereo paired unit, after development, and during subsequent viewing may, if required, be viewec within an appropriate viewing system.

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which Figure I shows in perspective, a view depicting a typical external configuration of the stereo camera; Figure 2 illustrates in perspective, a partial cut-away view depicting a typical internal configuration of the camera depicted in Fie. I; Figure 3 snows a plan, front elevation and partially sectioned side view of the camera depicted in Fig. 2, showing a typical arrangement ttat incorporates a film pack/cartridge with its film unit contents and other associated elements; Figure 5 shows a typical arrangement for a ready-mounted pair of film sections, -combined together to form a stereo film unit, to be associated with the camera depicted in Fig. 2.

Referring to the accompanying drawing, Fig. I depicts an external view of the body 37, of the stereoscopic camera. Referring to Figs. 2 and 3, the camera comprises a detachable back 3, allowing access for a film pack 8, without needing to disturb the rollers 9. Within the said pack are a set of film units 7, in this instance, each one containing a pair of 24 x 36 mm film frames. In Fig. 2, one of the exposed transparency film frames 6, of the primary film unit is depicted seated against its film frame mount buffer 5, it being concentric, or thereabout, with its own shutter and lens I3 and I4. Figs. 2 and 3, show the film frame mount buffer 5, also used as a location means for the film pack, enabling film units to be correctly aligned.The film pack will simultaneously locate onto the film mount unit buffer 5, and seat against its own buffer 4, in order to prevent excess pressure from being exerted against the film units.

In Fig. 3, D refers to a partially sectioned side view of the camera.

This configuration may utilize standard film units that each comprise a pair of 5 x 5 cm film frame mounts, temporarily combined together until after development, or the configuration may be adapted in order to incorporate film frame mounts that may be a larger or smaller size than 5 x 5 cm. These mounts can adapt to suit 36 x 36 mm, or thereabout, film frames, to be utilized within a modified camera configuration having an enlarged film frame buffer aperture and associated elements; or a converse effect can be arranged by adapting the film mounts to contain a smaller than standard film frame size with corresponding camera modifications; the focal length being altered accordingly.

This particular stereo camera configuration is capable of having its pair of lenses I4, one for each film frame of a pair, retain a separation distance between tneir centres, on a horizontal plane, equal to the average interpupiliary distance of an adult person, 64 mm, while remaining consistent with a required capability to expose successive pairs of full frame 24 x 36 mm, or thereabout, films within 5 x 5 cm mounts, each frame of a pair located side by eide behind and concentric, or thereabout, with its respective lens.

After pressing the shutter release button I9, the shutter I3, wallows each successive film unit 7, to be exposed and is ejected either automatically, actuated by the electric motor I2, via transmission ears 11, driving the rollers 9, or via a manual / mechanical arrangement (not shown).

The configuration provides the means to produce successive paired exposures on combined ready-mounted elide film units that, after development, do not need the operator to cut, sort out different stereo pairs or mount the films, prior to being viewed within an appropriate stereoscope.

The ready mounted film units can comprise either conventional diapositive film or an immediate developing transparency film medium. Each preceding film unit within its pack, may have ite light sensitive coating protected from unwanted light, during exposure of the primary film unit. After exposure within the stereo camera, each successive stereo film unit, containing conventional diapositive film, will be mechanically ejected from the camera and can be transferred directly into a light tight box, attached to the outside of the said camera, that may contain all of the exposed film units. The box will subsequently be detached and dispatched with its contents, for their development.

If an immediate developing integral structure transparency film unit is used, the conventional ejection rollers act to eject and instigate a developing process within the said film unit. If a conventional transparency film unit is used, modified ejection rollers might be used in order to eject successive film unit without adversely affecting the emulsion and transfer each one to an externally attached light tight storage box (not shown) that will eventually be detached for later development of the contents.

The pair of 45 degree angled plane mirrors I, are related to an eyepiece 2, and viewfinder I7, the latter incorporating an inner compensatory composition area that is within and concentric with the actual viewing area; that enables the total subject view to be composed and contained within the composition area, thus ensuring that each 2-D film element of the final stereogram will contain all of the information of the said eubject. The outer actual viewing area, as seen through the eyepiece, takes into account a cut-off aspect of each lens view.

In order to prevent the film emulsion from being adversely affected through contact, during ejection of conventional diapositive film units, the lower inner part of the film frame mount buffer 5, and the lower inner part of the film pack 8, can be provided with a relieved aspect giving a clearance.

The large semicylindrical hand grip IO, provides ease of handling; the customary spirit level 16, observed through the eyepiece via the viewfinder, helps prevent tilting and misalignment of the stereo images.

Fig. 3, depicts a conventional flash facility 20, a film urit positioning spring 27, and the ejection path 24, for each successive film unit.

Figs. 2-3, depict a version of the camera configuration with convenient fixed focus matched (for focal length and physical dimensions) lenses I4.

It may be made with lenses of smaller or larger than standard 45 mm focal length, preferably between 35 mm and 50 n, in order to provide a choice between a relatively wide or narrow angle of vision for each of the pair.

A 35 mx lens is frequently considered to be a desirable choice as a general lens and in particular for this type of small film format stereo camera, allowing the standard full frames to accomodate a greater amount of information than a 50 mm lens, for example, for a given camera viewpoint. Another attribute of this wide angle lens that is directly linked to its short focal length, is great depth of field; in combination with its ability to be particularly forgiving to camera shake, thus enhancing the stereo cameras potential for enabling a stereogram comprising two full frame pictures if required - to be produced that gives good overall picture sharpness, that is so important in order to produce successful stereograms.

An optional lens arrangement may consist of the pair being set at different focus positions, so that the sharpest elements of the resulting pictures combine to make the stereo image sharp overall.

A. relatively small aperture setting may be used with fixed focus lenses that1 when used in conjunction with an optional exposure meter, will relate to the manual shutter speed control 15, that together contribute, in general, to essential good overall picture sharpness, from infinity to, perhaps, 2-3 metres making for easily obtainable and consistently effective stereograms; thus rendering adjustable focusing arrangements unnecessary.

An optional customary coupled aperture adjustment control and coupled focusing control, may be provided. It is also customery to utilize a coupled shutter control. Whatever type of shutters are used, within this camera configuration, they must ensure that each film frame receives an identical exposure, if the photographic subjects that involve movement are to make effective stereograms. Manual or automatic function of the various adjustment controls, where applicable, may be incorporated into the camera configuration, as desired.

The overall concept is flexible, in that appropriate modifications may be made to the stereo camera configuration, in order to adapt an alternative conventional immediate developing transparency film medium that may or may not be ready-mounted, prior to exposure and uses a peel-apart system.

The camera configuration would ensure that the successive exposed films would not need to be sorted into appropriate stereo pairs after development, as would be the case using cassette roll film within a conventional camera.

A suitably adapted camera configuration would be capable of utilizing film frames of up to approximately 6 x 6 cm for each one of a pair of films, while retaining, if required, the relevant 64 mm lens separation distance. An appropriate focal length adjustment would be incorporated.

An associated processing roller arrangement might be one where they are located vertically and to one side of the configuration, thus enabling each successive pair of exposures to be pulled out transversely from one side of the camera via the processing rollers.

Referring to Fig. 5, the ready-mounted paired slide film unit is intended to be used within the stereo camera depicted in Figs. I-3. The unit comprises, in this instance, a pair of full frame 24 x 36 mm transparency films, each within its own mount; the pair temporarily combined together.

After exposure within the stereo camera, each one records upside down, its respective left and right lens view of the subject 2I; the left lens view contained within its mount 6, depicted on its exposed side.

After development and inversion of the combined paired unit, the exposed side facing away, the left eye image will be on the right hand side and the right eye image will be on the left hand side. Before they can be viewed correctly within a stereoscope, these images must be transposed so that each one is located within its appropriate slide holder to correspond with its respective left and right eye of the viewer.

Information may be provided on the film carrier unit, for guidance, suggestions enabling the operator to correctly orientate each detached film section in relation to a stereoscope. A convenient procedure to follow, after development, for correct inetallation within a stereoscope is as follows: The exposure side of the unit 6, is depicted as it would be positioned within the stereo camera; the images are upside down 28. Referring now to the viewing side of the unit showing its left and right eye views 25b and 25, respectively; they are depicted after development and prior to separation from their linking segment 26, and subsequent inversion of the individual mounts.These may be detached from the linking segment along the perforated lines 23, and then inverted through a I80 degree arc as shown at X, thus bringing the mounts the correct way round for locating and viewing within their corresponding slide holders on a stereoscope.

The inverted word TOP, at the base of this view, denotes what will be the top edge of each mount, after installation within a stereoscope, ready for viewing.

The unit may be adapted in order to contain an integral immediate developing colour transparency film medium. The processing reagent can be contained within a pouch 22, depicted here only as an optional alternative for when this particular medium is chosen and situated in a likely position, combined with colour dyes having a similar transparent quality to that of conventional colour transparency film, that would be capable of transferring from the negative side of a unit over to the positive side, resulting in a positive colour transparency image within the unit structure.

The regular mount size of 25b and 25, is 5 x 5 cm each one of the pair capable of containing any one of several film frame sizes to be compatible with a suitably adapted stereo camera. 'I35' sized 35 mm film will be used as a common base for some film frame formats. However, a 36 x 36 mm, or thereabout, film frame option provides stereograms giving the maximum dramatic stereo effect that can be obtained from film located within the regular mount size 25b and 25. The stereo camera configuration depicted in Figs. 2-3, will require only relatively basic alteration, to become an alternative stereo camera configuration option, in this instance, in order to provide the means to accommodate this particular film frame format. The focal length of the camera lenses may be changed in order to suit thie larger film area, but in this instance will not be deemed a necessary requirement, as any resulting image distortion will generally be considered to be insignificant. The aperture of the film frame mount buffer 5, and its associated elements will need to be enlarged to suit.

A variety of suitable materials might be utilized in the fabrication of the film mount unit structure. The means provided, in order to enable each mount 25b and 25, to be detached from its centre segment, can be different from that described. This provision is a desirable convenience, useful in the absence of an appropriate cutting device.

Claims (1)

1. I. A film and related stereo camera arrangement, in which two transparency film sections are mounted on a carrier, the film sections being spaced apart, to permit ready separation, one from the other after picture development. A first opening in the camera is provided for locating and aligning the carrier unit and means provided for exposing successive combined pairs of such ready-mounted film units. A second opening is provided for ejection of the exposed film units which may contain, if required, a particular full frame film format that is commensurate with a particular lens separation distance that the camera configuration is capable of achieving and that may be, if required, equal to the average interpupiliary distance of an adult person.

   2. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein the carrier may be provided with one or more different means for said separation after development and conveniently, such separation means might be either perforations or scored lines placed between the film sections, or the said carrier might remain plain; marks or lines depicting, if required, where cut may be made.

   3. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein a cartridge has a plurality of film units positioned one behind another.

   4. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein the carrier unit may be adapted in order to provide optional sizes of mount and or film frame pairs and conveniently, such a unit might comprise a pair of 5 x 5 cm mounts that are capable of containing one of several film frame sizes up to 36 x 36 mm or thereabout.

   An alternative pair of smaller mount film frames may be provided.

   5. A film and related stereo camera arrangement, as claimed in any one of claims 1-21 wherein preceding film units within their cartridge, are protected from unwanted light during exposure of the primary film unit and conveniently, such means might be a removable opaque member, that may lightly adhere to the back of each unit.

   6. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein information may be provided on the carrier unit, for guidance only, suggestions enabling the operator to correctly orientate each detached film section in relation to its respective film holder of an appropriate stereoscope and conveniently, such guidance might consist of printed or embossed words and or symbols.

   7. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein as an optional requirement, the camera may be adapted to incorporate a lens separation distance either more or less than the standard interpupiliary distance, preferably between 55-75 mm, or thereabout, in order to provide a realistic stereoscopic effect, if required, or an exaggerated stereo effect can be obtained relative to the increased lens separation distance chosen above standard.

   8. h film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein the camera may be adapted in order to provide the means to locate optional rizes of mount and or film frame pairs and conveniently, such a mount and film frame size might be 5 x 5 cm mounts, each containing a 36 x 24 mm, or thereabout, image on 'I35 sized 35 mm diapositive film.

   9. A film and- related stereo camera arrangement, as claimed in any one of claims I-2I wherein the camera may be adapted in order to provide the means to locate and utilize optional film mediums and conveniently, such a film medium might consist of immediate developing peel-apart transparency films, contained within a cartridge.

   10. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein the camera may be adapted to provide ejection rollers of a particular form, when used in conjunction with conventional diapositive film units and conveniently, the front roller in particular might have two inner segments along its length that are narrower in diameter than the concentric outer and central segments; or the front roller, in particular, might be formed from an appropriate material that will not adversely affect the film emulsion during ejection.

   II. A fila and related stereo camera arrangement, as claimed in any one of claims 1-2I wherein the camera may be adapted in order to provide the means to locate optional types of film cartridge and conveniently, one of these arrangements might consist of a stereo camera body with a detachable back enabling a film cartridge containing individual conbined pairs of ready-mounted slide film units, to be inserted into the back of said camera body and into position until contact is made with a cartridge buffer eo that the cartridge can locate and align onto a film frame mount buffer that also may seat the film frame mount primary unit, enabling each section of a pair of film frames spaced side by side, to be correctly aligned up against and concentric with their respective exposure box; that in turn are situated behind and concentric with, or thereabout, their respective lens; that after exposure, it and each successive film unit may be ejected along a path down and out through the base of the camera body.

   12. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein the suggested film frame mount buffer and a film cartridge, that might contain conventional diapositive film units, may be provided with a means enabling the emulsion of said film units to not be adversely affected during ejection and conveniently, such means might be a relieved aspect providing a clearance on the lower part of their inner surfaces thus preventing abrasive contact of the film emulsion during ejection.

   13. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein the camera may be adapted in order to provide the means to locate individual film sections that are ready-mounted and arranged side by side; separated from each other within a common cartridge or instead, two separate cartridges, located side by side with each one containing its own ready-mounted film section.

   I4. A film and related stereo camera arrangement, as claimed in any one of claims 1-2I wherein the camera may be adapted in order to provide the means to locate a sheet film holding device that will enable each sheet of its related film medium to be loaded and stereoscopicaliy exposed, one at a time.

   15. A film and related stereo camera arrangement, as claimed in any one of claims -2I wherein the camera may be adapted in order to provide the means to locate and utilize a particular film medium option and conveniently, such a film medium may consist of an integral immediate developing transparency film unit that will have a carrier adapted to incorporate an appropriate chemical development facility and a transparent protective 'window' covering member behind which will remain, after exposure and development, the visible image.

   16. A film and related stereo camera arraneement, as claimed in any one of claims I-2I wherein the carrier may be fabricated from any one or a combination of any of a variety of materials and conveniently, such a material might comprise a combination of card and plastic.

   I7. A film and related stereo camera arrangement, as claimed in any one of claims 1-21 wherein the camera ejection system nay be adapted to either provide an electronic or manual actuation.

   16. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein the camera may be adapted in order to provide an alternative ejection means instead of rollers, if conventional transparency film units are to be utilized.

   I9. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein a detachable magazine box may be externally attached to the camera. After each successive exposure of the film units, they may be ejected out of the camera and transferred to said magazine holder. If the film unit contains conventional transparency film, the magazine will be of a light excluding type.

   20. A film and related stereo camera arrangement, as claimed in any one of claims I-2I wherein the stereo film sections and associated carrier unit may remain intact, after development and during subsequent viewing, if required, within a transposing stereoscope or by projection using a modified procedure.

   2I. A film and related stereo camera arrangement, substantially as described herein, with reference to Figures I,2,3 and 5, of the accompanying drawings.