Design History of the Amplified Reality Headset (arh)
The idea of the arh has multiple origins, though one could say it emerged as a result of looking through the viewfinder of a camcorder and trying to navigate in space using only this image.
It was a short step to realize that two camcorders would be better than one. It was important that they be the same make and have specifications such as S-video, AV in/out, headphone socket, and capability of mounting external microphone or camera, accordingly two Canon MV6540i’s were acquired. This tied in perfectly with an already burgeoning interest in binaural recording and the influence of different frequencies of sound and light on the brain and body.
The use of two cameras, when carefully positioned, allows the viewer depth perception, or 3D vision, through the creation of parallax. This occurs aurally in much the same way.
But accurate 3D is only possible at a certain focal length, so that objects near and far appear doubled.
Also the viewfinder of a camcorder does not give an immersive sense of proximity but rather feels like looking through a tunnel into a miniaturised world. Essentially it consists of a lightproof box with a magnifying lens at one end, a tiny LCD screen at the other, and an appropriate distance between them.
The logical next step was to use the larger flip-out LCD panels in conjunction with some magnification.
There were many problems with this, for example the centralisation of the image by the magnifying lens, difficult viewing angle, distortion, etc. The process of research into cheap parts yielded the discovery of the fresnel lens. In particular a site called madlab showed attempts at making head mounted displays (HMD), and video projectors. The HMD was a pair of ski goggles with holes cut out the centre and a couple of mini TVs taped to the front. The LCD projector used a fresnel lens, an adjustable overhead projector (OHP) lens, an LCD screen, lights, and a fan.
There were many different plans and designs available on the net for making this kind of projector. Two small vinyl fresnel lenses were purchased from E-bay at a minimal price. About the size of a credit card they seemed promising, perhaps rather than directly looking through a magnifying lens, the image could be projected onto the internal screen of a helmet, enabling the use of polarized filters to create accurate 3D.
A prototype projector was designed in order to test the possibility. First a box was made to hold the camera, one side had a hole for viewing the LCD screen, the other side opened to allow access to the camcorder.
Another box was made that the first box could slide up and down in. At one end it was open, the other was closed with a small fresnel lens in the centre of the end panel.
In a dark room tests revealed it was possible to project an image on the wall without additional lighting. Different distances, both between the wall and the device, and between the LCD and the fresnel lens, produced greater or lesser clarity and magnification. At close distances a small clear image was projected, at further distances the image was larger but less clear.
Between these two extremes it was excellent, a discovery that was both exciting and disappointing, due to the insurmountable problem of focal length. The mean projecting point where the image was at its optimum necessitated a distance of at least 2 metres from the projecting surface, which itself would have to be large. It seemed that size alone would obstruct the possibility of projecting onto the inside of a helmet using polarized filters to achieve 3D.
The amount of equipment required for this project was both too heavy and too expensive. A fundamental re-think was required. What were the essential and the superfluous aspects of the arh? Was there a simpler and cheaper way of achieving the same effect? What equipment could be purchased within the personally financed budget?
The essential idea was to be immersed, and capable of movement, in a reality perceived only through technological media. To enable the recording of an audio-visual perspective that could be played back in different contexts or mutated using computer software.
Although the binocular and binaural functions were desirable, they were not necessary for the production of an immersive environment. Early cinema, with its one loudspeaker behind the screen, though obviously not as powerful as today’s Dolby surround sound, was still immersive in its own way – the audio-spectator is in fact engaged in the creative process of redistributing sound in relation to the visual image and an off-screen space.
Looking at the screen directly through the Fresnel lens was quite an interesting effect as it gave the illusion of depth perspective at the same time as a strange sense of unreality caused by the actual proximity to the screen and the enlarged pixilation. Internet research revealed that Fresnel lenses could be used to create collimated displays for flight simulators. This could solve the intractable problem of viewing length.
In the final analysis it was a lack of financial resources that necessitated an indefinite postponement of the 3D projecting model. After much deliberation, discussion with experts, and Internet browsing, a 7” LCD screen, a small 12-volt battery, and some leads, were purchased from ‘Maplins’.
The LCD screen needed to be adapted so that it could be part of a mobile headset. This meant plugging the 12-volt battery into the LCD screen and using its adaptor plug as a charger for the battery. Unfortunately the polarity was wrong and the LCD screen broke. This caused major setbacks and temporary employment was sought in order to retrieve the funds necessary for a second LCD screen.
Eventually this was possible and experiments could continue. A frame was constructed from cardboard to house a larger (cheap, vinyl) fresnel lens, a box was then made large enough to fit it, so that it could slide up and down. A box was made for the LCD screen so it could fit in the same adjustable manner. In the large box a hole was cut out for the head. This enabled tests to be carried out to measure the best distances between the LCD screen, the Fresnel lens, and the eyes.
Experiments revealed that at greater distances the image, though magnified more, would distort at the edges more, and at a smaller distance magnification was reduced and vision became difficult. The optimum distance was surprisingly small however, at xcm between the eyes and the lens, and xcm between the lens and the LCD.
This practical attempt also brought to light a problem of cables that had been overlooked. If the video signal was coming from the AV output there was no output for sound since it was interchangeable with the headphone output. This meant that the video had to come from the S-video terminal, and the sound from the headphone output, leaving no possibility of an external binaural microphone setup.
The only solution was to acquire the accessory microphone (Canon DM50) designed specifically to accompany the camcorder which fitted directly into a hot-shoe on the top. The shotgun microphone has a directional or stereo setting possibility and affords a far greater sound quality than the internal microphone, which records the engine noise of the camcorder.
These initial prototypes were made from cardboard (painted black) and, now the dimensions and distances had been ascertained, it was possible to begin constructing a more durable platform that could sustain the weight of the rest of the equipment. This was constructed from several different sizes of aluminium flat rods, steel nuts and bolts.
A replacement OHP lens (much higher quality acrylic fresnel encased in glass) was ordered from an obscure outlet in Surrey. First a frame was built around the fresnel lens to hose it and provide a platform for bolts. One side had four 3mm angled aluminium flat rods bolted together into a square, the other a piece of scrap aluminium cut into the shape of a picture frame.
The frame was then mounted in a larger frame, and struts were then attached to it in order to provide a platform for the LCD screen.
Bolts were filed down so they could slide into the wall fittings provided on the LCD screen, which could then be attached at a distance of xcm from the fresnel lens. Arms were then bolted to the large lens frame making two triangles around the head.
At first a system of straps was tested, inspired by the design of military night-vision wear. The weight of the fresnel lens and LCD screen at that distance from the face was too great to withstand however, and another solution was required. A cheap construction helmet was purchased and a square frame (xmm angled aluminium flat rod) built around and drilled into it.
The arms were extended in order to provide the length for counterbalance using the 12-volt battery at the back. The distance between the arms and the helmet frame was bridged using xmm angled aluminium flat rod.
Black card was bought and cut out to cover the frame of the LCD screen and block out light from it. On the other side of the fresnel lens an oblong viewing tube was attached for the same purposes. This meant that the viewer could see only the LCD screen, surrounded by blackness.
A platform for the battery was constructed that could slide up and down the arms. A battery charger, a small fan, and some lightproof curtain lining was bought. The fan was attached on one of the arms. The curtain lining was cut up and stitched together in order to make a cover for the arh. Lastly the counterbalance distance was ascertained and the battery platform attached.
Filming
When the arh was ready for use filming took place in the green belt to the North West of London, on the South coast of England near Beachy Head, and in central London. Environments and situations were sought which would be particularly affective, in terms of light and sound and differing frequencies or vibrations, the sun and the wind featured strongly, as did water and fire, and machines such as trains, engines and drills. Many different materials were audio-visually investigated, such as pebbles, bark, string, and metal. All the situations recorded were drenched in the interaction of sensation and evoked a synesthetic response. More importantly it was the movement of the body that the arh recorded, but this was not a human body, or a representation of subjectivity, but a cybernetic transformation, yielding an alien form, movement and perception.
Editing
Editing the five hours of captured material into a film for viewing was a massive task in itself, and consisted in constantly reviewing all the footage, repeatedly searching for clear sections of immersive movement with interesting audio-visual stimuli, and, more minutely, locating the irruption of an event within the vibratory milieu of that time-space, to serve as a pivot for the edit. The film moves from one scene to another by what Deleuze calls the ‘irrational cut’, a transition which nevertheless has a precise meaning.
The purpose of the arh had been to record real situations and to enable the re-immersion of others into the same audio-visual and proprioceptive stimuli. This could only be achieved by not treating the sound or image in any way, such as altering pitch or speed, trimming, enlarging, adding effects etc. The arh does not merely reproduce former situations but transforms environments through playback, and constitutes an audio-visual and noematic time travel. An eleven minute section of time-modified reality was therefore deemed appropriate (the remainder of the hour-long DV cassette is raw long cuts), here short sections of the immersive long cuts are sped up, slowed down and or reversed, and juxtaposed in quick rhythmic succession. These time manipulations produced interesting sonic and optical affects, not to mention a strong response of disjunctive recognition.
Exhibiting
An exhibition was held at ‘The Foundry’ in Old St. from the 6th of September to the 11th of several students from the Sonic Culture MA. ‘The Foundry’ is a bar and gallery space situated in an old bank, and it was very fortunate to procure the vault as a space for showing the arh. The vault is a chamber made of reinforced concrete deep in the ground and the acoustic properties (high reverberation) are incredible. Since the room offered such excellent possibilities it was decided to use a stereo for the amplification of playback, and some large speakers. The reverb of the room was so great the speakers were covered in black cloth to dampen the high end which would otherwise bathe the room in a wash of sound. One speaker was placed behind a chair, and another underneath, in order to provide vibration.
Visitors were introduced to the concept and the machine and offered to sample it live. In this case they could walk around, unfortunately the space was small, and visually uninteresting. Also the sound in this mode was only amplified by the camcorder and did not have sufficient power to withstand the reverb of the acoustic chamber. It was playback that was most successful in this space since it could use the room as a bass bin whilst maintaining the high end on the headphones.
Though there were some technical difficulties (the LCD sometimes turned itself off and access to it was not easy) and problems with putting the arh on, the response was excellent. A common complaint was the weight, and this could be its biggest drawback, but little could be done to reduce it within the budget and timescale. Many people began moving their heads as they watched the film, indicating immersion, some tried to touch things with their hands or feet, many laughed. Everyone had something to say about it afterwards and much of it very useful, given the kind of media clientele that frequent the establishment. ‘The Foundry’ was so interested in the arh it has been invited back for two weeks in December.
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