BEYOND THE SPATIAL PARADIGM:
TIME AND CINEMATIC FORM IN HOLOGRAPHIC ART

Eduardo Kac

Of all the new technologies that are changing the mediascape at the end of the century, holography is perhaps the medium that remains least understood by the general public and specialized art critics alike. The small number of mainstream exhibitions and published critical papers on holographic art reveals a yet uncharted territory.

One of the most common misconceptions about holography is the notion that the medium's primary visual property is that of producing "illusionistic" three-dimensional pictures -- a kind of spatial photograph, with an added dimension (1). The "naturalistic" misconception is usually grounded on unfulfilled expectations and unproductive comparisons with other media, when not to poor or inexistent research (2). I will go as far as to suggest that those who think of holography in these simplistic terms are just unaware of some of its most significant features and directions (3).

The goal of this essay is to dispel these delusions by demonstrating that, in fact, the holographic aesthetic experience is much more complex than it may seem at first. Holography may be thought as a perspectival system, but this approach is of no interest here. Rather, my goal is to reveal holography as a time-based medium, and to show in what circumstances it has been explored as such by artists. The observation of a few artists' work encircles the problem and suggests manifold approaches.

It is clear that aesthetic experiences are warranted in all cases to be discussed ahead; however, by no means will I suggest that scientific holograms, whenever mentioned, be read as artworks. If every artwork unfolds into aesthetic experiences, not all aesthetic encounters are provoked by artworks. The focus will be the issue of time, in a medium traditionally known (albeit little understood) for its spatial properties. The revelation of the range of the aesthetic and technical directions of the temporal experience in holography, it is my hope, will lead to a greater appreciation for the artistic potential of the medium.

EXPERIMENTAL HOLOGRAPHY, PHOTONIC CINEMA

In an article discussing the uniqueness of the digital moving image as distinct from other forms of cinema, Gene Youngblood wrote: "Cinema is the art of organizing a stream of audiovisual events in time. It is an event-stream, like music. There are at least four media through which we can practice cinema -- film, video, holography, and structured digital code --just as there are many instruments through which we can practice music. Of course each medium has distinct properties and contributes differently to the theory of cinema, each expands our knowledge of what cinema can be and do.(4)" This observation is of particular interest because it emphasizes holography as a time-based medium, and not as a three-dimensional imaging technique. However, as we shall see, time is manifested in holographic art not only as streams of images, but also as suspended clusters and discontinuous structures.

The prospect of digital holographic movies of the future notwithstanding, the multimedia nature of the computer compels us to a redefinition or, at least, to an expanded definition of what holography is -- or can be. As practiced by a small but increasing number of artists around the world, art holography asserts time, expressed as changes and transformations, as an aesthetic feature as important as the three dimensions of space. Created with computers or not, motion-based holograms become interactive events that can be perceived in any direction, forward or backward, fast or slow, depending on the relative position and speed of the viewer. Unlike the unidirectional "event-stream" of film and music, as mentioned by Youngblood, four-dimensional holograms are "buoyant events" with no beginning or end. The viewer can start looking at any point. Time is suspended from its extended continuum and can flow forward or backward.

Many holograms and holographic installations created today involve electronic image manipulation and digital synthesis, and draw from other artistic fields, such as photography, film, and video. These works explore time in unique ways and reveal a very important aspect of the medium. Most holograms created by scientists or commercial holographers are motionless, or at best have very limited motion, because their images usually aim at reproducing a virtual environment or object with the visual stability typical of traditional holography. Since the object in most holograms is three-dimensional and stationary, many holographers use the computer to make stationary virtual objects. Holograms thus produced emphasize space instead of time, and volume instead of movement.

We need not examine in detail the technical development of automatic imaging systems, from early nineteenth century until now, to understand that it created the historical, aesthetic, and material conditions for the current digital synthesis of holographic images. In a clear development of painting's aspiration to truth and veracity, photography first attempted to fix images as seen in nature. The camera obscura, used by painters for centuries, became the photographer's essential tool. In the next stage, photographers tried to capture different moments of an action. Muybridge's analysis of motion and Marey's chronophotography paved the way for cinema. As a consequence, Edison and the Lumière brothers showed that images representing motion could not only be recorded as stills but set to motion themselves, allowing us to see representations of the recorded events as a temporal flux. Much later, video technology instantiated the recording, eliminating the temporal gap between the action and its playing back and, therefore, reinforcing the congruity between the representation and the reference. More recently, personal computers seem to have demolished photography's truth ambition by allowing anyone to manipulate photographic images and to easily recombine them in any desired way. If photography forced painting to redefine its direction in the beginning and middle of the nineteenth century, today computers have a similar impact on photography. How does holography fit in this context? Holograms are already routinely synthesized from secondary sources, including silver photography, video, film, sensing devices, and computer graphics.

MIXED MEDIA, MIXED MEMORIES

American artist and holographer Dean Randazzo has used computers, video, film and photographic techniques to create complex holographic artworks of distinct beauty (5). Pieces such as "Pasqualina #2" reveal how the artist unites highly personal imagery to a sharp technical sensibility, layering images that define their space by an intricate kinetic articulation of light.

Randazzo creates for each piece a paradigm of photographic and cinematographic records of family events clearly defined in time. He then displaces the time reference by associating images of events that could have taken place as many as fifty years apart. Many of the old original negatives, prints and film footage that Randazzo manipulates are in a state of decay, their silver coatings having been partially dissolved in time. Randazzo sees in these images a way to suggest the symbolic dissolution of memory. In his holograms, tenuous memories, fading faces, partially erased bodies and dissolving environments open a gateway to the viewer's own recollections.

Drawing his attention to the hologram's capability for storing information non-locally rather than to produce three-dimensional images, Randazzo uses more than ninety different pictures in "Remnant 1 and 2", a piece in which he combines photographic prints and stereograms made from old home movies around the central images of a sailor and a bride. Stereograms, these holograms produced from many sequential two-dimensional images which usually create a three-dimensional stereoscopic picture, are distorted and transformed beyond their common use in Randazzo's work.

Most of Randazzo's holograms are to be seen from both sides because the artist wants to use the film plane not just as a physical reference but as a "transitional device". The viewer should never expect to see the "other side" of the image on the "other side" of the hologram. In Randazzo's work the space is outlined by motion and the relative position of images, not by stability of forms. In "Trace" (1990), a single-pane piece viewed from both sides, the artist employs several dynamic forms, including an image of a walking figure both in negative and positive and a spinning metal artifact that rotates more than 360 degrees around its vertical axis, disobeying conventional stereoscopy. The action takes place in several planes and the structure of the space reveals itself as the viewer sees both sides and activates several other real and virtual images that shift in multiple directions simultaneously.

In some of his works, Randazzo uses computer imaging techniques either to make texture animation or to manipulate the gray scale (and other features) of old prints and movie frames. In "Reliquary study # 2", an image of a woman's face is subjected digitally to successive tonal changes. Simultaneously, an image of a small artifact rotates slowly in its visual integrity, since this time stereoscopy was preserved. The computer imagery double exposed with the stereogram produces a complex animation, as if decades of decomposition were compressed in a holographic event.

Randazzo's typical working method starts with selecting images fixed in the past by means of light. He then manipulates these faint images with other photographic processes, sometimes with film editing or computer techniques. The resulting images are finally manipulated holographically and become propagating light again. Randazzo's reminiscent images seem to show, with their chromatic delicacy and collapsing structure, that there is a whole world to be discovered when fragments of memory are brought into light.

LIGHT CHOREOGRAPHIES

One of the most intriguing and fascinating styles of holographic work revolves around the modulation of luminous structures whereby light itself is controlled as a new visual medium. The art of light in motion, devoid of referential subject matter, acquires in holography yet an unexpected sense of wonder. Artists such as Rudie Berkhout, Paul Newman, and Vito Orazem create subtle orchestrations of light forms that are at once communicative of human spiritual qualities and revelatory of unforeseen luminescent vistas. In their works, the sense of play is extended from the dynamic manipulation of light forms to an interplay between the work and the viewer, since it is through the latter's movements that the holographic images are activated. With holography these artists explore not the action of light on surfaces, as in the photogram, but the actual manipulation, recording and reconstruction of light phenomena.

A pioneer of holographic art who started his experiments in the mid '70s, Dutch artist and holographer Rudie Berkhout, who lives in New York, has combined an interest for the spatial properties of the hologram with delicate manipulations of fluid images (not stable objects). (6) Since the beginning he intentionally avoided the use of immediately recognizable forms, to invite the viewer, instead, to new worlds he created within the parameters of holographic space and time.

His holograms often engage the viewer both for their new sense of composition, in which empty space defies the inevitable link between three-dimensionality and matter, and carefully controlled movement, which can oscillate between the violent fusion of images, as in "Sketching Away" (1979), to the more delicate undulation of disembodied colors. Many of Berkhout's holograms, such as Ukiyo (1983), for example, invoke the appearance of a spacescape, or a lightscape, suggesting through receding lines or protruding visual elements (that actually come out of the picture plane) an extended vista into a subjective domain. But these are not contemplative spacescapes. Because images are often in motion in his holograms, the viewer is invited to explore them dynamically, discovering as he or she moves in front of the piece subtle chromatic and spatial changes. These often reveal new elements not seen at first, which can be experienced simultaneously by multiple viewers. The artist sees in these simultaneous structures, which can only be perceived as such in holography, a form of revelation of dimensions of human experience that cannot be rendered visually otherwise.

He also creates other works that show self-contained light forms with very subtle colors. His "Light Flurry" (1992) series, for example, is composed of what in other media might be identified with gestural brushstrokes, but which in holography becomes more difficult to describe. These abstract forms are obtained through the reflection and refraction of light on irregular surfaces, and are further chemically manipulated to produce pastel hues. Rudie Berkhout uses the hologram not only to capture the form of this irregular diffraction of light, but also its behavior. This enables the viewer to see the modulation of light in a constant state of transformation.

While Berkhout is fascinated by natural phenomena and tries to bridge the new medium of holography with traditional painting subject matters, such as the landscape, British artist and holographer Paul Newman focuses, in his series "Light Forms" and "Siva's Dance", on the unique properties of pure light itself (7). In Newman's holograms it is impossible to identify specific forms or compositions, because the artist works with the evanescent behavior of diffracted white light to produce fleeting apparitions. These insubstantial luminous phenomena are in flux and invite the viewer to move vigorously before the work. The slightest change in point of view is enough to activate their patterns of oscillation.

Newman identifies visual clarity, light intensity and color saturation as holography's unique qualities, and sets out to combine them in infinite possibilities. His images are not premeditated. They result from an intense experimentation in the laboratory. Newman makes coherent light (laser) pass through arrangements of lenses, blown, cut and broken glass, opaque masks, and other materials with an eye for the ways in which this coherent light will break up when the final piece is at last illuminated and reconstructed under white light. This exploration requires a certain level of pre-visualization, but by no means can the artist fully determine beforehand what the behavior of the work will ultimately be. The discoveries and unforeseen results experienced by the artist, once determined to be revelatory and stimulating, are shared with the viewer in the form of a finished piece.

As much as white light breaks up prismatically under the experimental control to which it is subjugated by Newman, it is also recombined by the artist to yield chromatic harmonies that are as ethereal as the visualized dancing forms themselves. Paul Newman realizes the power of holography to create images that are suspended between the imagined and the experienced, and he pursues this dance of spectral hues with a unique sensibility that unites intent, chance, and constructive or destructive decision making.

Rejecting staid representational holography as too close to illusionism, which detracts from an appreciation of the medium's most unique qualities, artist and holographer Vito Orazem echoes Paul Newman's search for an aesthetic of light in motion (8). Orazem, who was born in the former Yugoslavia and who now lives in Germany, has been working since 1987 in collaboration with German holographer Thomas Lück. While artists such as Harriet Casdin-Silver, Melissa Crenshaw, Sidney Dinsmore, Margaret Benyon and Susan Cowles have transformed the otherwise sterile mimetic character of holography into powerful subjective, and often political statements, it is true that most of the representational work regularly exhibited under the rubric of 'holographic art' lacks the visual intelligence and conceptual precision found in Berkhout's, Newman's and Orazem's work.

Orazem and Lück have created a series of installations in which they integrate holography, video and computer animation. In these installations, the hologram is not used straightforwardly as a display device, as in Berkhout's work, or as a means to record and replay the photonic dance of colors, as in Newman's case. Orazem and Lück's holograms do not contain any kind of imagery themselves. They are what is technically known as HOEs, or Holographic Optical Elements. These are holograms that do not display a picture, but instead are used to act as a lens, mirror, or a complex optical component. Rarely are HOEs used in artworks, and more rarely even in the radical and creative way developed by the German team.

Their main visual arrangement comprises a video monitor, with noise or black and white computer animations, and a large HOE, which is placed in front of the monitor. Instead of a halogen bulb, the monitor -- with its changing forms, pulsating contrasts, and moving elements -- becomes the light source for the HOE. This is carefully designed to take light in and manipulate, distort, and multiply it in numerous visual echoes, further blending colors and creating an overall calm and meditative meaning. The result is a cinematic spectacle that blends the temporal linearity of computer animation with the spatial and chromatic dimensionality of holography. The artists have created many works based on this principle. HOE-TV, for example, used only noise on the monitor. It was created in 1990 and shown the same year at the European Media Arts Festival, in Osnabrück, Germany.

Orazem and Lück are also very interested in integrating their installation into indoor settings, and further investigating the relationship of new media and architecture. The artists have incorporated HOEs into walls and floors, activating the space with multiple monitors and digital animations. In their installation "Diffracted Wall", from 1992, they experiment with the idea of an immaterial wall, which replaces the traditional opaque physical barrier with new holographic visual properties and dynamic qualities. "Diffracted Wall" was shown in 1992 at the exhibition "Light and Architecture", in Ingolstadt, Germany. With their work, Orazem and Lück want to create a new kind of experience in which the immateriality of light, once manipulated dynamically, brings together the fields of design, architecture, and the visual arts.

HOLOGRAPHIC FILM AND VIDEO

Orazem and Lück's work is probably as close as holographic art gets to cinema, before invading the field of filmmaking once and for all. If one was to write the history of holographic cinematography, one would have to trace its scientific roots to the early 1960s (9). Back then, many experimental setups were developed in laboratories around the world in which a special kind of laser (known as 'pulsed laser', due to the very short pulses it produces), was used to record moving images. Traditional cameras were adapted by removing lens and shutter, since the film had to be exposed to the scene directly. The early short films thus produced required special viewers and could only be seen, through small windows, by one person at a time. A laser had to be used to play back these films, normally in setups that brought back memories of Edison's kinetoscope.

In 1969, physicists in the United States produced a 70 mm 30 second-holographic film of tropical fishes swimming in an aquarium (10). In the early '80s, a team of French scientists at the Franco-German Defense Research Establishment (ISL), at St. Louis in France (11), intensified their previous research on holographic cinematography and showed the first film reconstructed with the technique known as 'reflection' holography (invented in 1962 by Yuri Denisyuk, in St. Petersburg, to enable reflective display of holograms in white light). From 1983 on, they shot several short holographic movies in 35mm and 126 mm film (12). Most of these holograms had to be seen with a laser. Working with members of ISL, in France, English sculptor Alexander, who now lives in the US, created in 1986 a 80-second 126 mm fiction film called "The Beauty and the Beast". Inspired by Jean Cocteau (La Belle et La Bête, 1945), and not the Disney Studios, Alexander portrayed Beauty as a model and Beast as an artist. As the artist himself acknowledged, the film showed more the limitations of the process as an artistic form than its potential (13). By contrast, George Méliès' A Trip to the Moon, from 1902, had the epic length of 21 minutes.

Before Alexander, holographic films of a non-scientific nature were produced only by a couple of French filmmakers with a background in philosophy, Claudine Eizykman and Guy Fihman, who develop their research at the Experimental Cinema Laboratory, LEAC, Université Paris VIII, (14). Their first films, in 35 mm and 70 mm, with up to 24 frames per second, were produced in 1984. In 1985, they showed a film, "Circular flight of sea gulls", at the monumental exhibition "Les Immatériaux", at the Center Georges-Pompidou. This was meant as a homage to Ettiene-Jules Marey, a forerunner of cinema who also worked with this theme. That same year, they showed publicly in Paris a new 126 mm film, called Un Nu, a palindrome that translates literally as "A Nude". This 5-minute film shows a mummy, who slowly turns and frees itself from the bands that contain it. Little by little, the bands reveal the flesh of a female nude, that emerges from within the green light that surrounds it. The viewer can push a button and play the movie backwards, observing the young woman become a mummy again. Hence the title in palindromic form. This movie must be seen inside an apparatus that is almost 7 feet high, 24 inches wide, and 28 inches deep, and exhibits the same technical limitations that frustrated the English sculptor.

Instead of dismissing the idea of holocinema altogether, Alexander drew from his first experiment with ISL scientists and set out to develop a new strategy for experimental holographic filmmaking, based on a simpler technique, known as 'integral hologram' (or 'multiplex'). (15) Integral holograms became very popular in the '70s, due to their ability to use film footage, shot with regular 35 mm or 16 mm ciné cameras, to create stand-alone 360-degree animated holographic scenes viewable in regular white light. The most well-known multiplex hologram is "Kiss II", shot in 1974 by Lloyd Cross in collaboration with Pam Brazier. This 180-degree integral hologram, shot from 540 ciné frames, portraits ms. Brazier winking and blowing a kiss at the viewer. Multiplex holography saw its popularity dwindle in the '80s, to virtually disappear in the '90s, with few exceptions.

As Lloyd Cross had done in collaboration with Bonnie Kozak in the late '70s, when he produced the first reel-to-reel integral movie, Alexander decided to remove integral holograms from their cylindrical container, and stretch and splice as many as fourteen of them in a roll. He developed a simple motorized mechanism that, with light source firmly in place, rolls the holograms from right to left through a 7" X 9" window, showing series of animated scenes sequentially. A lens in front of the hologram enlarges the images to approximately 12" X 16". The irretrievable linear flow of time, responsible for the drama unique to traditional cinematography, doesn't apply. If the viewer moves to left or right, he or she can see glimpses of the next scene, or see again the one perceived a second ago. "The Dream" (1987), his most accomplished holographic film, has original music composed by Alexander himself and runs for 8 minutes. It shows loosely linked sequences that evoke chimeric mental states. Anamorphic ballerinas, a man walking upside down inside a big head, a fusion of a human body with a landscape, couples dancing and dissolving in space, and a child playing with falling cubes, are some of the scenes that structure the movie. The holograms were shot by Sharon McCormack, an early collaborator of Lloyd Cross.

In Japan, holographer Jun Ishikawa and filmmaker Shigeo Hiyama, from Tama Art School, working with enginner Kazuhito Higuchi, from Nippon Telegram and Telephone Corporation, have been working since 1992 on yet another approach to the same basic idea of running actual holograms before the viewer's eyes to create motion pictures. Their initial projects, however , were closer to the zoëtrope than to the kinetoscope. At first, they shot holograms of inanimate objects that were manipulated frame-by-frame. They sandwiched three hundred 10 mm X 200 mm holograms between two acrylic drums, with a diameter of approximately 3 feet. The drum was rotated and the film illuminated with a low-power red laser, at a rate of up to 24 frames per second. This 40-second animation, entitled "ORGEL - A Boy's fantasy", tells the story of a boy who dreams of playing a music box (ORGEL) made by a nymph (16). The researchers employed eight cuts and experimented with several techniques, including stop-motion, panoramic shots, enhanced depth perception, up-shots, and overlaps. This piece, which also raises unavoidable comparisons with late nineteenth-century cinematic representation devices, is a good indication of the infancy of holographic cinema, both as a technology and as an art. They have developed other alternative systems, including a 35 mm camera that records moving images with a pulsed laser, and what they call a "retro-directive screen", which enables viewers to see the animations more comfortably. All of their film experiments revolve around the same theme described above. Their longest movie to date runs for 2 minutes and 50 seconds, at 10 frames per second.

The current scenario for the development of real holographic movies is not very encouraging. Victor Komar, a Russian scientist based in Moscow, developed as early as 1976 the first actual holographic cinematographic system, using lenses to record moving images, a special projector that employs a mercury-cadmium lamp, and a holographic screen for the projection of the movies (17). Four people could see his first 47-second film, in its monochromatic yellow hue, at the same time. The subject, a young woman holding a bouquet of flowers, was perceived in full four-dimensions (the three of space and that of time), with naked eyes. This was just like the films we see regularly in movie theaters, except that the viewer could move around in the seat and perceive spatial details of the scene. The viewer could, for example, move to the side and see the whole face behind the bouquet. Komar's first holographic color film, with a duration of 5 minutes, was produced in 1984. In 1990, I was told personally, in New York, by Yuri Denisyuk, that Komar's research was interrupted due to budget cuts. More recently, Hans Bjelkhagen, the Swedish physicist who is a leading expert in pulsed and color holography, told me that Komar has retired and that no one is carrying on his research. On the other hand, scientific research has been successfully carried out since 1989 at MIT to develop 'holographic video' (18). While several laboratory prototypes have been produced, no artistic or fictional work has been created. Most of the animated imagery developed so far represents arbitrary subjects or objects of interest to those entities sponsoring the research, such as automobiles.

New technologies undoubtedly open up unprecedented opportunities for artists. However, they are not, in themselves, an indication of the directions experimentation in visual arts will take. Photography had to wait more than a century to be accepted in art circles, and even longer to become incorporated into the artist's general repertoire of tools, in equal terms with painting and sculpture. Video did not have to wait this long. Holography will benefit tremendously from the passage of time, and one day will be understood, accepted, and seen as just another tool. Discussions concerning the validity of the medium as an art form will be long forgotten, and the work of individual artists-holographers, which is what really matters, will be discussed without conceptual hindrances. What will be of holographic cinema is hard to say. Predictions about the future of holographic cinema have failed miserably, so it could be a futile rhetorical exercise to try to anticipate the state of maturity this technology will reach as an art. But then again, the Lumière brothers could never dream of Sergei Einsenstein, Orson Welles, or Alain Resnais.

NOTES

1 - New York Times' art critic Charles Hagen wrote that holograms are "strange pictures, which usually take the form of glass plates on which murky photographic images marked by an intense illusion of three-dimensional space can be seen." See "Holograms: The Defense Resumes", in New York Times, November 29, 1991. In a more serious and diligent discussion of the holographic image, John Fisher -- who promptly acknowledges the chasm between holography and photography -- still reveals a very limited understanding of the complexity of the art hologram: "Holograms are illusions which insist that something exists in space in the total absence of any object at all, and they are not private. (That allows us to retain sanity in the face of the ultimate deception.)." See "Some New Problems in Perspective", by John Fisher, in Philosophy and the Visual Arts, Andrew Harrison (ed.), D. Reidel Publishing Company, 1987, pp. 303-316.

2 - See Tulla Lightfoot, "Contemporary Art-World Bias in Regard to Display Holography: New York City", in Holography as an Art Form, Louis Brill (ed.), special issue of Leonardo, Vol. 22, Nos. 3/4, 1989, pp. 419-423. Also: Barilleaux, René Paul. "Holography and the Art World," Leonardo (1992), Vol. 25, No.5, pp. 417-418; and Maline, Sarah. "Eluding the aegis of science: art holography on its own," Society of Photo-Instrumentation Engineering (SPIE) Vol. 1600 (1991), International Symposium on Display Holography, pp. 215-219.

3 - For a more thorough discussion of some of holography's most significant features see my "On Holography" (in New Media Technologies, Ross Harley (ed.), AFTRS, New South Wales, Australia, 1993, pp. 122-139; and "Aesthetics and Representation in Holography", SPIE Vol. 2333 (1995), pp. 123-137. For a discussion of time in my own holographic work, see: Kac, Eduardo. "Holopoetry and Fractal Holopoetry: Digital holography as an art form", in Holography as an Art Form, Louis Brill (ed.), special issue of Leonardo, Vol. 22, Nos. 3/4, 1989, pp. 397-402; "Recent experiments in holopoetry and computer holopoetry," SPIE Vol. 1600 (1991), International Symposium on Display Holography, pp. 229-236; "Holopoetry, Hypertext, Hyperpoetry," SPIE Vol. 2043 (1993), Holographic Imaging and Materials, pp. 72-81. Also, on the World Wide Web: http://www.uky.edu/FineArts/Art/kac/kachome.html.

4 - Youngblood, Gene. "Cinema and the code", Leonardo, Computer Art in Context Supplemental Issue, 1989, p. 27.

5 - Randazzo, Dean. "A Discussion of Two Holograms: Pasqualina and Trace," Leonardo, 1992, Vol. 25. No.5, pp. 493-495; "Loss and recovery: some thoughts on the nature of my holographic art," SPIE Vol. 2043 (1993), Holographic Imaging and Materials, pp. 98-100.

6 - Berkhout, Rudie. "Holography: Exploring a new art realm -- Shaping empty space with light," in Holography as an Art Form, Louis Brill (ed.), special issue of Leonardo, Vol. 22, Nos. 3/4, 1989, pp. 313-316.

7 - Newman, Paul. "Holography and computer graphics: A marriage of convenience?", SPIE Vol. 2043 (1993), Holographic Imaging and Materials, pp. 123-125.

8 - Orazem, Vito. "Holography as a material for light: Radical Holography," SPIE Vol. 1600 (1992), International Symposium on Display Holography, pp. 160-165; also: "Holography as an element of the media architecture," SPIE Vol. 2333 (1995), International Symposium on Display Holography, pp. 168-177.

9 - Leith, Emmeth and Upatnieks, Juris. Journal of the Optical Society of America, Vol. 53, 1963, p. 1377, and Vol. 54, 1964, p. 1295.

10 - Jacobson, A.D. et alli. "Motion Picture Holography," Applied Physics Letters, Vol. 14, 1969, pp. 120-122. See also: Youngblood, Gene. Expanded Cinema (Dutton: New York, 1970), pp. 399-414.

11 - Smigielski, Paul et alli. "Cinéma en relief: les promesses de l'holographie". La Recherche, Vol. 6, N. 163, Fev. 1985, pp. 240-242. Also: "Progress in Holographic Cinematography". SPIE Vol. 600 (1985), pp. 186-193.

12 - Salmon, Pippa and Sen, Kamala. "Holographic movies bring a fourth dimension to holography - time!". Holographics International (N. 2, Winter 1988), pp. 26-27.

13 - Alexander. "Development of integral holographic motion pictures," SPIE Vol. 2333 (1995), International Symposium on Display Holography, pp. 187-197.

14 - Bloch-Morhange, Lise. "Cinéma en relief: L'Aventure de la cinéholographie continue...". Le Monde, 7/13/1985. See also the loose sheet "Profondeur Simulée", in the catalogue of "Les Immatériaux", Centre Georges- Pompidou, Paris, 1985; and "Le cinéma holographique: entretien épistolaire avec Claudine Aizykman et Guy Fihman", Jacques Kermabon, in "Les Théories du cinéma aujoud'hui" (Paris: Cerf, 1988), pp. 144-150.

15 - Lloyd Cross, a California-based scientist, invented the integral hologram in 1973, after combining three innovative holographic techniques: the stereogram, perfected by DeBitteto in 1969, the rainbow hologram, invented by Benton in 1968, and the 360-degree hologram, simplified by Jeong in 1967. See: "HoloStories: Reminiscences and a Prognostication on Holography," Lloyd Cross and Cecil Cross, Leonardo (1992), Vol. 25, No.5, pp. 421-424.

16 - Kazuhito Higuchi, Jun Ishikawa and Shigeo Hiyama. "Holographic movie: the first step to holographic video". SPIE Vol. 1667, Practical Holography VI (1992), pp. 44-51; "An improved experimental holographic movie to estimate picture quality for holographic television". SPIE Proc. Vol. 1914, Practical Holography VII, pp. 197-205, 1993; "Experimental holographic movie to estimate picture quality for holographic television (III)." SPIE Proc. Vol. 2176, Practical Holography VIII, pp. 57-64, 1994; "Experimental holographic movie IV: the projection-type display system using a retro-directive screen." SPIE Proc. Vol. 2406-03, Practical Holography IX, forthcoming, 1995.

17 - Komar, Victor. "Progress on the Holographic Movie Process in the USSR". SPIE Vol. 120, Three-Dimensional Imaging (1977), pp. 127-144. Also: "Holographic Movie System in the USSR". Holosphere, Vol. 15, No. 2., Summer 1987, pp. 9-11; and "Works on the Holographic Cinematography in the USSR". SPIE Vol. 1183, Holography '89 (1990), pp. 170-182.

18 - Lucente, Mark and Galyean, Tinsley. "Rendering Interactive Holographic Images", SIGGRAPH '95 Technical Proceedings, paper #202 (ACM, New York, 1995), pp. 387-394; P. St.-Hilaire, S. A. Benton, M. Lucente, J. D. Sutter, and W. J. Plesniak, "Advances in holographic video", in SPIE Proceedings #1914 Practical Holography VII, (SPIE, Bellingham, WA, 1993), paper #1914-27; P. St.-Hilaire, S. A. Benton, M. Lucente, and P. M. Hubel, "Color images with the MIT holographic video display," in SPIE Proceedings #1667 Practical Holography VI, (SPIE, Bellingham, WA, 1992), paper #1667-33; Mark Lucente, "New Approaches To Holographic Video", Proceedings of Holographics International '92, SPIE Proceedings #1732, paper #1732-48, (SPIE, Bellingham, WA, 1992); S. Benton, "Elements of holographic video imaging,", SPIE Vol. 1600 (1991), International Symposium on Display Holography, pp. 82-95.

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