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Abstract
IMAX grew out of the large and multiple screen film experiments produced for Expo ’67 in Montréal.
Since then, it has become the most successful large format cinema technology. IMAX is a multiple
articulation of technological system, corporate entity and cinema practice. This article shows how
IMAX is reintroducing a technologically mediated form of ‘tourist gaze’, as elaborated by John Urry,
into the context of the institutions of museums and theme parks. IMAX is seen as a powerful exemplar
of the changing role of cinema-going in contemporary post-Fordist culture, revealing new
conjurations of older cultural forms and practices. In particular, the growth of this brand of
commercial cinema runs parallel to a blurring of the realms of social and cultural activity, referred to
as a process of ‘dedifferentiation’. This article gives special attention to the epistemological
dimensions of IMAX’s conditions of spectatorship.
This is about the IMAX motion picture film format. For the company responsible for this
format, see IMAX Corporation. For the car known as the Hyundai IMAX in some markets, see
Hyundai Starex. IMAX (an acronym for Image MAXimum) is a motion picture film format and a set
of cinema projection standards created by the Canadian company IMAX Corporation and developed
by Graeme Ferguson, Roman Kroitor, Robert Kerr, and William C. Shaw. IMAX has the capacity to
record and display images of far greater size and resolution than conventional film systems. Since
2002, some feature films have been converted (or upgraded) into IMAX format for display in IMAX
theatres and some have also been partially shot in IMAX. IMAX is the most widely used system for
special-venue film presentations. As of 31 December 2013, there are 837 IMAX theatres in 57
countries.
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Chapter 1.
Introduction
The desire to increase the visual impact of film has a long history. In 1929, Fox introduced
Fox Grandeur, the first 70 mm film format, but it quickly fell from use. In the 1950s, the potential of
35 mm film to provide wider projected images was explored in the processes of Cinema Scope (1953)
and Vista Vision (1954), following multi-projector systems such as Cinerama (1952). While
impressive, Cinerama was difficult to install. During Expo 67 in Montreal, Kroitor’s In the Labyrinth
and Ferguson’s Man and the Polar Regions both used multi-projector, multi-screen systems. Each
encountered technical difficulties that led them to found a company called “Multiscreen”, with a goal
of developing a simpler approach.
The single-projector/single-camera system they eventually settled upon was designed and
built by Shaw based upon a novel “Rolling Loop” film-transport technology purchased from Peter
Ronald Wright Jones, a machine shop worker from Brisbane, Australia (see U.S. Patent 3,494,524).
As it became clear that a single, large screen image had more impact than multiple smaller ones and
was a more viable product direction, Multiscreen changed its name to IMAX. Tiger Child, the first
IMAX film, was demonstrated at Expo '70 in Osaka, Japan.
The first permanent IMAX installation was built at the Cinesphere theatre at Ontario Place in
Toronto. It debuted in May 1971, showing the film North of Superior. The installation is still in place,
however, Ontario Place is on hiatus for redevelopment. During Expo '74 in Spokane, Washington, an
IMAX screen that measured 27 m × 20 m (89 ft. × 66 ft.) was featured in the US Pavilion (the largest
structure in the expo). About five million visitors viewed the screen, which covered the viewer’s total
visual field when looking directly forward. This created a sensation of motion in most viewers, and
motion sickness in some. An IMAX 3D theatre also is in operation near the former Expo 67 site at
the Montreal Science Centre in the Port of Old Montreal.
The first permanent IMAX Dome installation, the Eugene Heikoff and Marilyn Jacobs
Heikoff Dome Theatre at the Reuben H. Fleet Science Centre, opened in San Diego's Balboa Park in
1973. It doubles as a planetarium. The first permanent IMAX 3D theatre was built in Vancouver,
British Columbia for Transitions at Expo '86, and was in use until September 30, 2009. It was located
at the tip of Canada Place, a Vancouver landmark. As China is now the second largest market after
USA with roughly 25 IMAX theatres located throughout the country, IMAX aims to attract more
viewers by decreasing the admission prices in China. In January 2015 the IMAX theatre at the Pacific
Science Centre in Seattle close for renovation. The current film IMAX projector will be removed and
replaced with an all-digital system.
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Chapter 2.
Analog Technical Aspects
2.1 IMAX Camera:
The IMAX cinema process increases the image resolution by using a large-frame film; in
relative terms, of producing a sharp movie image, a frame of 35mm film produces approximately six
thousand lines (6K) of horizontal resolution, but an IMAX-format film frame produces approximately
18 thousand lines (18K) of horizontal resolution.
To achieve such increased image resolution, 65mm film stock passes horizontally through the
IMAX movie camera, 15 perforations at a time, which at 24 frames per second means the film moves
through the camera at 102.7 metres per minute (just over 6 km/h). In a conventional 65mm camera,
the film passes vertically through the camera, five perforations at a time, or 34 metres per minute. In
comparison, in a conventional 35mm camera, 35mm film passes vertically through the camera, at
four (smaller) perforations at a time, which translates to 27.4 metres per minute.
In the Todd-AO 70mm-format of widescreen cinema, the image area of a 65mm film-frame
is 48.5 mm × 22.1 mm (1.91 in × 0.87 in); in the IMAX-format of widescreen cinema, the movie
image is taller than it is wide, given the film-frame dimensions of 69.6mm × 48.5mm (2.74 in × 1.91
in). To match the standard image resolution of the moving image produced with the film-speed of 24
frames per second, an IMAX film requires three times the length of (negative) film stock required for
a 65mm film of comparable scope and cinematic technique.
Fig 1: An IMAX cinema camera, displayed at the National Media Museum, Bradford, U.K.
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2.2 Film Formats:
The IMAX format is generically called "15/70" film, the name referring to the 15 sprocket
holes or perforations per frame. The film's bulk requires horizontal platters, rather than conventional
film reels. IMAX platters range from 1.2 to 1.83 meters (3.9 to 6.0 ft.) diameter to accommodate 1 to
2.75 hours of film. Platters with a 2.5 hour feature film weigh 250 kilograms (550 lb.).
IMAX uses ESTAR-based print film in their 15/70 rolling-loop film projection systems.
ESTAR-based print film provides greater precision. The chemical development process does not
change the size or shape of ESTAR print film, and IMAX's pin registration system (especially the
camera mechanism) does not tolerate either sprocket-hole or film-thickness variations.
Fig 2: Film Formats.
Gauge refers to the width of the film, and there are four commonly in use for camera films: Super 8,
16 mm, 35 mm, and 65 mm.35 mm is most popular for feature films, commercials and US television.
It can be printed to 35 mm print film or scanned or transferred on a telecine.16 mm film is typically
supplied in single perforated format except for use in high-speed cameras, which use double
perforated film.
Fig 3: Comparison of Conventional Screen and IMAX Format
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The Super 16 format is typically used for low to medium budget feature films, where it can be blown
up to 35 mm release prints. It is also widely used for television production, where its aspect ratio fits
16:9 wide-screen format well. Super 8 is available as both negative film and reversal film, supplied
in self-contained cartridges. The 65 mm format is used as a camera film gauge for making prints on
70 mm print film for widescreen presentation such as IMAX and OMNIMAX.
2.3 Image Format and Aspect Ratio:
The film image format describes only the image aspect ratio (shape). 35mm or 65 mm gauges can
have several image formats, because aspect ratio is independent of gauge. The aspect ratio is the
relationship between the width and height of an image. An image that’s twice as wide as it is high
has an aspect ratio of 2:1.
Rules for Aspect Ratios
Aspect ratio = width divided by height
Aspect ratios are independent of the film gauge (the width of the film)
Aspect ratios are expressed two ways:
As a ratio with the height as unity, for example 1.78:1 (used for film)
As a simple ratio with the width and height as whole numbers, for example 16:9, or
16x9 (used for widescreen or HDTV)
The industry standard for 35 mm theatrical motion pictures remained a constant 1.37:1 between the
introduction of sound and the introduction of CINEMASCOPE in 1953.
Fig 4: The full picture shows the 1.37:1 aspect ratio. The dotted lines show the border of the very
similar 1.33:1 ratio.
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1.33:1 is the standard TV/Video ratio (expressed as 4:3 in the TV industry). It was based on the 1.37:1
aspect ratio. These two ratios are so similar that they are sometimes used interchangeably. This is
also the aspect ratio of regular 16 mm and Super 8.In the United States, there are two aspect ratios
commonly used for 35 mm film projection: 1.85:1 (flat) and2.40:1 (scope). Theatre owners who
wanted to create a wide screen developed 1.85:1; they did this by cutting of the top and bottom of the
1.37:1 image.
Fig 5: 1.85:1 known as “Flat”.
The 2.40:1 image was developed from the 2.35:1 CINEMASCOPE system. Special anamorphic
camera lenses are used to squeeze the image during capture. A similar lens is used to expand or un-
squeeze the image during projection. The original 2.35:1 image was later modified to 2.40:1.
Fig 6: 2.40:1 known as “Scope”.
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A common aspect ratio in Europe is 1.66:1, the native aspect ratio of Super 16. This is because many
films shot in Europe were shot on Super 16 and then blown up to a 35 mm print. The 1.66:1 ratio is
very similar to the current standard for HDTV, 1.78:1 or 16x9.
Fig 7: 1.66:1
Fig 8: 1.78:1
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Two 70 mm formats are also in current use. 70 mm wide at 2.2:1 and IMAX, which is 1.43:1. Both
are projected onto much larger screens than 35 mm formats.
2.4 Shooting Formats:
4-perf
The most common shooting format is 4-perf 35 mm. Feature films with aspect ratios of 1.85:1
and television programs may use this format. The cinematographer frames for the final aspect ratio,
and that part of the image is used for electronic transfer to video or projection in theatres.
Fig 9: 4-perf frame.
4-perf scope
With 4-perf scope the image is photographed through special lenses that squeeze the image.
The image is then “un-squeezed” during projection.
Fig 10: The entire area will become the 2.40:1 image when un-squeezed.
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4-perf Super 35
Super 35 uses the whole frame of film, including the space usually reserved for the soundtrack.
From this full frame, a 2.40:1 extraction is made in the intermediate process, optically or digitally, to
produce a squeezed negative for printing.
Fig 11: The aspects that can be taken from a Super 35 mm frame.
3-perf
The 3-perf format was originally developed for television. Advancing the negative 3 perfs at
time instead of 4 eliminated the extra space between frames. That extra space had been helpful in
splicing 35 mm negatives together, but such splicing is seldom used in television production. It was
once impractical for feature films but digital intermediates have made this a viable format for feature
films.
Fig 12: 3-perf on 35mm fame
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2-perf
This format is similar to 3-perf, but the camera pulls down 2 perfs instead of 3.2-perf is used
to create a 2.40:1 image with a minimum amount of film. Like Super 35, the image must be digitally
or optically enlarged to a 4-perf animorphic intermediate/negative. This process was once called
TECHNISCOPE.
Fig 13: 2-perf on 35mm fame.
VISTAVISION (8-Perf)
VISTAVISION is a 35 mm horizontal format with an eight-perforation pull down (across),
which was typically used with high quality background plates in special ejects work. The camera
aperture is approximately 1.5:1 (37.7x 25.2 mm).
Fig 14: Vista Vision.
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Super 16
The image resulting from Super 16 is the same height as standard 16 mm, but the image
extends into the perforation area. The native aspect ratio of Super 16 is 1.66:1, which is nearly
identical to HDTV (1.78:1).When Super 16 is blown up to 35 mm, an aspect ratio of 1.85:1 is usually
taken from it. Super 16 is currently the most common shooting format for many independent films,
television productions, advertising, music videos, and documentaries.
Fig 15: Super 16.
16 mm
The Standard 16 mm image has the same aspect ratio as the original 35 mm academy format.
It’s typically used for 4:3 television origination. The image is symmetrical on the centreline, and the
area to the right on single-perf print stock can be used for an optical soundtrack. Almost all 16 mm
cameras can be used with single-perf film. Double-perf stock is also available, but is typically used
for shooting with specialized high-speed cameras. It can be used for normal sync shooting, but only
in 1.37:1 format (not for Super 16).
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Fig 16: Regular 16 mm image on single-perf stock and double-perf stock.
Super 8
Once considered an amateur format, Super 8 is now used for eJect in promos, documentaries,
and many other applications. It is also used as an eJective tool for teaching film. It is supplied in self-
contained cartridges.
Fig 17: These are scans of Super 8 film. On the left is a negative and on the right is reversal.
65 mm
Images made on 65 mm film have a 2.2:1 aspect ratio. Release prints are made on 70 mm
print film. This was once necessary to accommodate six magnetic sound tracks on the edges of the
film. Today a double-system sound system is used with separate CDs having 6-track sound controlled
by a time code printed on the film.
65 mm IMAX
IMAX and OMNIMAX productions use 65 and 70 mm film but with a horizontal image and
a 15-perforation pull-down (across) for very large-screen shows.
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2.5 IMAX Soundtrack - double-system
In order to use more of the image area, IMAX film does not include an embedded soundtrack.
Instead, the IMAX system specifies a separate six-channel 35 mm (1.377 inch) magnetic film,
recorded and played back on a film follower locked to picture, just as Vitaphone had been (utilizing
16-inch 33 1/3 RPM electrical transcription discs) in the early 20th century, and was the same
technology used to provide the 7-channel soundtrack accompanying films photographed and
exhibited in the Cinerama process in the mid-1950s.
By the early 1990s, a separate DTS-based 6-track digital sound system was used, similarly
locked to the projector by a SMPTE time code synchronization apparatus, the audio played off a
series of proprietarily encoded CD-ROM discs. In the late 1990s this system was upgraded to one
using a hard drive which carries a single uncompressed audio file containing the 6 channels. These
are then converted directly to analogue rather than using a decoding method such as DTS.
Like conventional theatres, IMAX theatres place speakers both directly behind the
acoustically transparent screen and around the theatre to create a "surround sound" effect. IMAX also
provides a "top centre" speaker in addition to the centre speaker found in conventional theatres. This
extra channel allows the sound mix engineers to take advantage of the screen's greater height.
Fig 18: IMAX speakers (front left corner)
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IMAX theatres require a sound system able to produce believable effects and operate
reliably at unusually high power levels. The IMAX sound system by Sonics provides extremely high
sound quality that does full justice to the unique film presentation. A Sonics sound system operates
in an environment which is quite different acoustically from most other theatres. The IMAX film
program depends on the optimum performance of the combined projector and sound system to
achieve maximum audience impact.
In 1988, IMAX acquired Sonics Associates Inc. as an affiliate. Alabama based Sonics is a
world leader in sound system design and offers customers the benefits of more than 26 years of
research and hands-on experience in the IMAX theatre network.
Fig 19: laser aligned surround sound system.
The 35mm sound dubber with 6 channel magnetic IMAX sound. To the left all the amps are
located.
I will try to describe how the audio system works, from projector to the audience. Sound for
an IMAX or IMAX Dome film program historically has been supplied on 35mm sprocket magnetic
film which runs at 90 feet per minute (45.7 cm/sec.). The sound reproducer, often called a dubber, is
located in the projection room. This multi-channel playback unit was originally developed for film
studios where banks of them are used when mixing sound tracks. It provides exceptionally high
quality sound reproduction and feeds the six channel system plus sub-bass through IMAX TAC-86
multi-channel audio control computer. Maximum playing time is one hour with a reel capacity of
5000 feet (1500 m).
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An interlock circuit between the projector and the reproducer maintains frame-to-frame
synchronization of projected picture and sound. A rotary shaft encoder required for synchronizing
audio reproduction is installed in the IMAX projector.
Most of the new IMAX films are now using the IMAX digital sound DDP designed by Sonics.
DDP is short for Digital Disc Playback. The system is a digital sound source specifically made for
IMAX. Sonics uses compact disc technology to create the highest quality sound delivery possible
today. Wide frequency response, dynamic range and the accurate perception of time are the attributes
of DDP. A frequency response of 20 – 20.000 Hz is maintained over the entire audio spectrum of ten
octaves. Six octaves is found in conventional cinemas. Three CD’s are used for each soundtrack, one
CD for every 2 channels. The audio is sent to the Sonics TAC-86. From the TAC-86 the signal is sent
to the computer-controlled 1/3 octave equalization unit, developed for IMAX. This unit matches the
sound system performance to suit the acoustics of the particular theatre in which it is installed. The
equalization can also be used to compensate the response of particular films for optimized playback
in a particular theatre.
After the equalization, the signal is sent to the power amplifiers. The amps deliver more than
2000 watts per channel. The entire system is more than 15000 watts. The six audio channels are fed
to a 4-way JBL speaker array. Every section is equipped with JBL models no: 2404 H (Ultra-High
Frequency), 2445 J (Wide Range), 2123 H (High Power Low Frequency), and 2245 H (Medium
Efficiency Extended Bass). They are located to give strong directional effects and placed as follows:
Channel 1 Left rear (theatre), Channel 2 Left screen, Channel 3 Centre screen, Channel 4 Right screen,
Channel 5 Right rear (theatre), Channel 6 Top of screen.
A special subwoofer with 8 JBL model 2245 H (Medium Efficiency Extended Bass) in one
enclosure (a cabinet huge like a caravan) is provided to extend the range of the main channels and
reproduce such sounds as rocket launches, thunder, close-flying aircrafts, etc. at loudness which
approaches that of the original sound source. Because the lowest pitched sounds that human can hear
are also felt, this enhances the realism, making the audience feel they are actually experiencing the
event.
The subwoofer is equipped with 8 JBL 2245 H woofers. The group of sub-bass speakers,
located at the front of the theatre behind the screen, is fed a mix of low frequency sound derived by
the TAC-86 from all six channels. The power amplifier for sub-bass is more than 3000 watts. The
price for the Sonics sound system is more than 300,000 $.
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2.6 IMAX Projectors:
Drawing the large film through the projector presented challenges for both the camera and the
projector. Conventional 70 mm systems were not steady enough for the 586× magnification. On the
projector side, William Shaw adapted an Australian patent for film transport called the "rolling loop"
by adding a compressed air "puffer" to accelerate the film, and put a cylindrical lens in the projector's
"aperture block". The projector uses a vacuum to pull the film into contact with this lens. Thus the
"field flattener" flattens the image field. The lens is twice the height of the film and connects to a
pneumatic piston so it can be moved up or down while the projector is running. This way, if a piece
of dust comes off the film and sticks to the lens, the projectionist can switch to the clean side of the
lens at the push of a button. The lens also has "wiper bars" made of a felt or brush-like material which
can wipe dust off the lens as it moves up or down. IMAX projectors are pin stabilized, meaning four
registration pins engage the perforations at the corners of the projected frame to ensure perfect
alignment. Shaw added cam-controlled arms to decelerate each frame to eliminate the microscopic
shaking as the frame "settled" onto the registration pins. The projector's shutter is open around 20%
longer than in conventional equipment and the light source is brighter. The xenon short-arc lamps are
made of a thin layer of fused quartz and contain xenon gas at a pressure of about 25 atmospheres
(367 PSI); because of this, projectionists are required to wear protective body armor when changing
or handling these in case the lamp breaks (e.g., due to a drop to the floor) because of the danger from
flying quartz shards when propelled by the high pressure of the xenon gas within. An IMAX projector
weighs up to 1.8 tonne (2 short tons) and is over 178 cm (5.8 ft.) tall and 195 cm (6.4 ft.) long.
Fig 20: IMAX 2D and 3D digital projection system.
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IMAX Corporation has released four projector types that use its 15-perforation, 70 mm film
format: GT (Grand Theatre), GT 3D (dual rotor), SR (Small Rotor), and MPX, which was designed
for retrofitted theatres. In July 2008, the company introduced a digital projection system, which it has
not given a distinct name or brand, designed for multiplex theatres with screens no wider than 21.3
m (70 ft.). All IMAX projectors, except the standard GT system, can project 3D images.
2.7 IMAX Theatre:
IMAX theatres are described as either "Classic Design" (purpose-built structures), or
"Multiplex Design" (retrofitted auditoriums). Classic IMAX theatre construction differs significantly
from conventional theatres. The increased resolution allows the audience to be much closer to the
screen; typically all rows are within one screen height; conventional theatre seating runs 8 to 12 screen
heights. Also, the rows of seats are set at a steep angle (up to 30° in some domed theatres) so that the
audience is facing the screen directly.
A standard IMAX screen is 22 m × 16.1 m (72 ft. × 53 ft.), but can be significantly larger.
The world's largest IMAX screen is in Darling Harbour, Sydney, Australia, and measures 35.7 m x
29.7 m (117.1 ft. x 97.4 ft.).
Fig 21: IMAX screen vs. standard screen.
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Chapter 3.
IMAX Variations
3.1 IMAX Dome / OMNIMAX:
In the late 1960s the San Diego Hall of Science (now known as the Reuben H. Fleet Science
Centre) began searching North America for a large-format film system to project on the dome of their
planned 23.16 m (76.0 ft.) tilted dome planetarium. The standard IMAX projector was unsuitable for
use inside a dome because it had a 3.65 m (12.0 ft.) tall lamp house on top. IMAX Corporation
redesigned its system, adding an elevator to lift the projector to the centre of the dome from the
projection booth below. Spectra Physics designed a suitable lamp house that took smaller, 46 cm (18
in) lamps and placed the bulb behind the lens instead of above the projector. In 1970,[17] Ernst Leitz
Canada, Ltd. (now ELCAN Optical Technologies) won a contract to develop and manufacture a
fisheye lens projection system optimized to project an image onto a dome instead of a flat screen.
Fig 22: OMNIMAX
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The dome system, which the San Diego Hall of Science called OMNIMAX, uses films shot
with a camera equipped with a fisheye lens that squeezes a highly distorted 180° field of view onto
the 65 mm IMAX film. The lens is aligned below the centre of the frame and most of the bottom half
of the circular field falls beyond the edge of the film. The part of the field that would fall below the
edge of the dome is masked. When filming, the camera is aimed upward at an angle that matches the
tilt of the dome. When projected through a matching fisheye lens onto a dome, the original panoramic
view is recreated. OMNIMAX wraps 180° horizontally, 100° above the horizon and 22° below the
horizon for a viewer at the centre of the dome. OMNIMAX premiered in 1973 showing Voyage to
the Outer Planets (produced by Graphic Films) and Garden Isle (by Roger Tilton Films) on a double
bill.
IMAX has since renamed the system IMAX Dome. However, some theatres continue to call
it OMNIMAX.
OMNIMAX theatres inhabit theme parks and North American museums, particularly those
with a scientific focus, where the technical aspects of the system may be highlighted as part of the
attraction. The projection room is often windowed to allow public viewing and accompanied by
informational placards like other exhibits. The screen may be a permanent fixture, such as at the
Museum of Science and Industry in Chicago, Illinois, Carnegie Science Centre in Pittsburgh,
Pennsylvania, the Franklin Institute in Philadelphia, Pennsylvania, the St. Louis Science Centre,
Boston's Museum of Science, Richmond's Science Museum of Virginia, Birmingham, Alabama's
McWane Science Centre and US Space and Rocket Centre in Huntsville, AL and Great Lakes Science
Centre in Cleveland, OH; or lowered and raised as needed, such as at the Canadian Museum of
History (where it shares an auditorium with a standard IMAX screen).
The entire dome can be raised to show flat screen features and lowered for dome features.
For the flat screen theatres, before the feature begins, the screen can be backlit to show the speakers
and girders behind it. While the majority of museum installations focus on educational and
documentary films, on special occasions, entertainment films are also shown, such as Charlie and the
Chocolate Factory at the Oregon Museum of Science and Industry. The largest in North America are
at Liberty Science Centre in Jersey City, New Jersey and the Telus World of Science in Vancouver,
BC, both of which have dome screens 27 metres (89 ft.) in size.
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3.2 IMAX 3D:
To create the illusion of depth, the IMAX 3D process uses two separate camera lenses that
represent the left and right eyes. The lenses are separated by a distance of 64 mm (2.5 in), the average
distance between a human's eyes. Two separate rolls of film are used to capture the images they
produce. The IMAX 3D camera weighs over 113 kg (249 lb.). By projecting the two films
superimposed on the screen and using one of several available methods to direct only the correct
image to each eye, viewers see a 3D image on a 2D screen.
One method is to use polarizing filters to oppositely polarize the light used in projecting each
image. The viewer wears glasses with polarizing filters oriented to match the projector filters, so that
the filter over each eye blocks the light used to project the images intended for the other eye.
In another method, the two projections rapidly alternate. While one image is being shown, the
projection of its mate is blocked. Each frame is shown more than once to increase the rate and
suppress flicker. The viewer wears shutter glasses with liquid crystal shutters that block or transmit
light in sync with the projectors, so each eye sees only the images meant for it.
Several of the early films that had been produced in digital 3D for release in conventional
theatres were also presented in IMAX 3D, including Avatar, Gravity and The Amazing Spider-Man.
3.2.1 IMAX 3D camera:
Fig 23: IMAX digital 3D camera.
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Back in the film days, IMAX pushed the limits of cinematography with film frames large enough to
capture the kind of detail necessary for its huge screens. And now the company has gone the same
route with digital.
"Transformers: Age of Extinction," which debuted Friday, is the first feature film to be shot
with IMAX’s own high-resolution 3D digital video cameras.
Fig 24: portable light weight IMAX 3D digital camera.
The company would share only some details about the IMAX 3D Digital Camera design, but
evidently IMAX felt it necessary to go beyond what's possible with cameras from companies like
Arri, Red, Sony, Canon, and Panasonic.
"Imax uses a custom 4K-horizontal sensor that is physically the largest of all commercially
available cinema camera sensors," the company said. Physically larger sensors can capture more
information, in particular a better range of dark and light detail, and the 4K horizontal resolution
means each frame of imagery is about 4,000 pixels wide.
3.2.2 Quick Facts:
IMAX® has developed the first fully integrated dual 65mm 4K digital large-format 3D
camera.
The IMAX® 3D Digital Camera delivers stunning image quality and is smaller, lighter and
easier to use than other 3D digital camera systems on the market.
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The IMAX® 3D Digital Camera is a true 4K stereo camera. This means that both the left eye
and right eye images are captured at full 4K resolution.
Transformers: Age of Extinction is the first feature film to ever use the new IMAX®3D
Digital Camera.
Exclusively in IMAX® theatres, sequences filmed with the IMAX® 3D Digital Cameras will
be presented in a 1.9:1 aspect ratio – offering moviegoers 26% more of the image than
standard cinemas for a truly immersive IMAX® 3D experience.
What’s unique about the new IMAX® 3D Digital Camera?
As part of IMAX’s commitment to innovation and providing filmmakers with the highest-
quality technology, IMAX developed the first fully integrated dual 65mm 4K digital large-format 3D
camera. The IMAX® 3D Digital Camera delivers stunning image quality and is less than half the
weight of other 3D digital camera systems on the market. The IMAX® 3D Digital Camera will
provide filmmakers such as Michael Bay with versatility that only 2D digital cameras have been able
to deliver in the past. In Transformers: Age of Extinction, the production team was able to capture
chase scenes and helicopter shots in high-resolution 3D in a way that previously impossible.
Exclusively in IMAX® theatres, sequences captured with this camera will expand to fill more of the
IMAX screen with unprecedented crispness, clarity, colour and 3D for a truly immersive experience.
What is the resolution of the IMAX 3D digital camera?
The IMAX® 3D Digital Camera is a true 4K stereo camera. This means that both the left eye
and the right eye images are captured at full 4K resolution.
How does the IMAX 3D Digital Camera compare to the IMAX 2D & 3D film cameras?
For more than 40 years, IMAX®’s 15perf / 65mm film cameras have been the highest-
resolution cameras in the world – delivering 10x more resolution than 35mm film. IMAX® designed
the IMAX® 3D Digital Camera as a complementary tool to its other 2D and 3D IMAX® film camera
systems as well as other camera technology that filmmakers may be using. Filmmakers typically use
several different types of cameras on set for different types of shots so IMAX wanted to be able to
provide them with the right tool for the right job to help achieve their creative vision. While digital is
advancing at a rapid pace, IMAX®’s 15perf / 65mm film cameras continue to be the industry gold
standard in terms of resolution and it expects they will to continue to be for quite some time. For this
reason, IMAX® is continuing to build more of these cameras to meet the demand it is seeing among
today’s leading Hollywood filmmakers.
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3.3 IMAX HD:
Variations on IMAX included the 48 frames per second IMAX HD process, which sought to
produce smoother, more lifelike motion, while also reducing the blurring of moving objects, by
doubling the normal film rate. The IMAX HD system was tested in 1992 at the Canada Pavilion of
the Seville Expo '92 with the film Momentum. Higher production costs, and the high "wear-and-tear"
on the prints and projectors, doomed the IMAX HD system, but, not before many theatres had been
retrofitted to project at 48 frames, especially in Canada, in order to play Momentum. In the 1990s
theme parks in Thailand, Germany, and Las Vegas used IMAX HD for their Motion Simulator rides.
The Disney parks attraction Soarin' over California features a modification of both IMAX HD and
IMAX Dome, projecting in 48 frames per second. Although The Hobbit trilogy has been shown in
IMAX DMR at high frame rate, it is unknown if the IMAX HD system has been used.
Production issue: The doubled IMAX HD frame rate means that each IMAX HD reel lasts half as
long, and the logistical implications of this reach throughout the film production chain. IMAX
production by default is at least 3 to 5 times more expensive than common 35mm production. The
further increase in IMAX HD has prevented significant adoption.
3.4 Digital IMAX:
Because 70mm film and projectors are costly and difficult to mass produce, IMAX debuted a
digital projection system in 2008. It uses two projectors that can present either 2D or 3D content in
DCI or IMAX Digital Format (IDF) (which in itself is a superset of DCI). As of 2012, IDF uses 2K-
resolution Christie projectors with Texas Instruments' Digital Light Processing (DLP) technology
alongside parts of IMAX's proprietary formats. The two 2K images are projected over each other to
make the image brighter.
The digital installations have caused some controversy, as many theatres have branded their
screens as IMAX after merely retrofitting standard auditoriums with IMAX digital projectors. The
screen sizes in these auditoriums are much smaller than those in the purpose-built auditoriums of the
original 15/70 IMAX format. These theatres charge the same premium pricing as the purpose-built
IMAX theatres, resulting in consumer confusion.
Another disadvantage is the much lower resolution of digital IMAX compared to traditional
IMAX film, which is estimated to be up to 8,700 lines of vertical resolution on the camera negative
and 4,500 on a release print. Some reviewers also note that many non-IMAX theatres are already
projecting films at 4K resolution, while digital IMAX has deployed both 2K and 4K products.
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Despite these concerns, IMAX has consistently chosen to hold to a uniform marketing position of
"The IMAX Experience" regardless of the various underlying technologies and screen sizes. Some
high profile figures such as film critic Roger Ebert and others also actively voiced their concerns. On
February 3, 2012, IMAX announced that it had selected Barco as the primary supplier of projectors
for the next seven years. In late April 2012, IMAX began testing a new 4K laser-projection system,
based on patents licensed from Eastman Kodak. Like the film and digital systems, it uses two
projectors but it has been said to improve over the smaller digital screens by retaining the traditional
IMAX aspect ratio and to allow films to be shown on screens 36 m (120 feet) wide or more. The laser
projector will be available to exhibitors in the fourth quarter of 2013.
The format has also aided in the company's worldwide growth, especially in Russia and China.
Mainly because the system facilitates inexpensive distribution of IMAX features, the company has
recently announced that they are re-renovating specially selected locations around the world to
present both 70mm analog as well as digital presentations. To do so, IMAX has, with another,
currently unknown, business partner, developed a rail system that allows the projectors to be moved
in and out if there is either a full-frame film print available or a digital-only release. These theatres
were prepared in time for the release of The Dark Knight Rises in July 2012.
3.5 Use in Hollywood productions:
Before the end of the 1990's, theatrical features were deemed impossible to run in the IMAX
venues at the time, as there was a technical limitation on the size of the film reel where films had to
be run around two hours. Originally IMAX and Pixar were considering to release Toy Story in IMAX
3D, but the results of the tests displayed that the render resolution could not match to the size of the
IMAX image. DreamWorks in the early 2000's wanted to re-release Shrek in IMAX 3D, but this too
was cancelled as a result of creative changes in the studio. These failed attempts at re-releases did
inspire IMAX to experiment and improve their ability in presenting computer-animation in their
theatres. Their compilation Cyber World was the result, which contained new original animation and
IMAX-presented versions of computer animated tests and music videos. Cyber world even presented
open-matte 3D versions of the bar sequence from Antz and the Homer3 segment from The Simpsons,
both coincidentally were animated at Pacific Data Images.
Walt Disney Pictures became the first studio to release theatrical films in the IMAX process.
Released on New Year's Day in 2000, Fantasia 2000 was the studio's first IMAX release and the first
theatrical feature to be presented in IMAX theatres. It was originally planned as a standard theatrical
release, but in agreeing with the company to release the film, the IMAX sound system incorporated
a multi-channel and multi-layer stereo system for the orchestrated soundtrack, similar to the Fanta
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sound system Walt Disney used for the original film decades ago. The company agreed to Disney's
terms and conditions to gain the exclusive first showings of the film. These included a limited
engagement of 4 months (from January 1 to April 30) and 50% of the box office receipts. Not all
IMAX cinemas were prepared to accept Disney's terms to present the film; however, following the
IMAX release, a standard 35mm run followed in June at regular theatres.
Fig 25: Michael bay using the IMAX 3D for shooting.
Although Fantasia 2000 had a Luke-warm financial run, the critical praise for its use of the
IMAX format convinced Disney to put more releases in the giant-screen format in the pipeline. In
2002, IMAX re-issues of Beauty and the Beast and The Lion King were released in select theatres
over the winter and Christmas seasons of that year. New digital masters were created from the original
CAPS production files and select scenes of animation were cleaned up to make use of the high
resolution IMAX film negatives. Treasure Planet was also released in select IMAX theatres and was
the first theatrical film to be released in regular and IMAX theatres simultaneously. But all of these
releases had underwhelming box office returns and Disney cancelled later big-screen re-releases,
including Aladdin.
With the unveiling of the DMR process (see below), Warner Bros. Pictures especially
embraced the format beginning in 2003 with the two Matrix sequels, Reloaded and Revolutions. Since
The Prisoner of Azkaban in 2004, Warner Bros. began releasing the Harry Potter film franchise in
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IMAX to strong financial success. Also in 2004 the studio released Robert Zemeckis' motion-capture
film The Polar Express in IMAX 3D. Polar Express became the most successful film to be released
in IMAX theatres, producing at least a quarter of the film's gross of $302 million from fewer than 100
IMAX screens. Success for Warner Bros. and IMAX followed in later years with I Am Legend,
Happy Feet, Batman Begins and The Dark Knight. Progressively other studios became further
interested in releasing films in IMAX through the DMR process and have earned success through it.
In 2009, J. J. Abrams' Star Trek was released for initially two weeks in IMAX venues in May and
opened to $8.3 million dollars. The IMAX opening weekends of The Avengers and Harry Potter and
the Deathly Hallows Part 2 have since grossed $15 million.
Though they weren't filmed with IMAX cameras, Skyfall and The Amazing Spider-Man were
optimized for IMAX digital screens when they were released. Both movies were filmed in high-
resolution cameras and the digital negative ratio was equal to that of the IMAX Digital frame. Skyfall
increased the visual information of the entire film while Amazing Spider-Man optimized the finale
battle with the Lizard. James Cameron's Titanic when it was restored and re-released in theatres also
specially made an open-matte version for IMAX. In 2010 after years of successful IMAX DMR
releases, Warner Bros. signed a deal to release up to 20 feature films in IMAX up to 2013, including
educational documentaries that were in production. The deal is currently set to finish with the second
part of The Hobbit in 2013.
3.6 IMAX DMR (Digital Media Remastering):
IMAX's proprietary DMR (Digital Media Remastering) process allows conventional films to be up
converted into IMAX format. This special digital intermediate technology allowed films shot on
35mm for conventional theatres to be shown in IMAX venues. In 2002, Star Wars Episode II: Attack
of the Clones and an IMAX-format re-release of the 1995 film Apollo 13, were the first official
applications of the DMR process. Because of the projection limitations at the time, Apollo 13 and
Attack of the Clones had to be edited down from their original length. As IMAX updated the system
and expanded the size of the platters, the later DMR releases did not have this limitation; current
platters allow a run time of up to 175 minutes.
Reviewers have generally praised the results of the DMR blow-up process, which are visually
and audibly superior to the same films projected in 35mm. But some filmmakers, such as producer
Frank Marshall, point out that DMR blow-ups are not comparable to films created directly in the 70
mm 15 perf IMAX format, and that directors Ron Howard and George Lucas expected better. They
note that the decline of Cinerama coincided roughly with its replacement by a simpler, cheaper,
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technically inferior version, and view DMR with alarm. IMAX originally reserved the phrase "the
IMAX experience" for true 70 mm productions, but now allows its use on DMR productions as well.
After The Lion King in 2003, no Hollywood studio engaged in re-releasing and restoring
classic films through the IMAX DMR process until 2012 although ongoing conversion of new
releases continued and continued to grow in number. James Cameron's Titanic underwent both 3D
conversion and DMR conversion to 3D in 2012 as did Men in Black 3. In August 2012 IMAX and
Paramount Pictures announced a one-week exclusive re-release of Raiders of the Lost Ark on
September 7, 2012, to promote the release of the Blu-Ray collection. The film, before it underwent
DMR, was already restored in a 4K digital intermediate with 7.1 surround sound from the original
negative. The process for IMAX theatres, like with the complete restoration, was supervised by
Steven Spielberg and sound designer Ben Burt. "I didn't know if the 1981 print would stand up to a
full IMAX transfer, so I came expecting a sort of grainy, muddy, and overly enlarged representation
of the movie I had made years ago," Spielberg said. "I was blown away by the fact that it looked
better than the movie I had made years ago." For other DMR releases and re-releases see List of
IMAX DMR films.
3.7 Feature films partially shot on IMAX cameras:
Some recent features have employed IMAX cameras for select scenes, however no full-length
feature film has yet been shot entirely using IMAX cameras due to the numerous difficulties presented
with the format – the cameras are much larger and heavier than standard cameras and as they are
noisier it makes dialogue recording difficult. The cameras have short film loads ranging from 30
seconds to two minutes and the cost of the film stock is much greater than standard 35mm film.
The Dark Knight Features six sequences (a total of 28 minutes) shot using IMAX. According
to the film's press notes, this was the "first time ever that a major feature film has been even partially
shot using IMAX cameras". Even before Dark Knight, Nolan had wanted to shoot a film in the IMAX
format, and he also used it for quiet scenes which pictorially he thought would be interesting. Nolan
said that he wished that it were possible to shoot the entire film in IMAX: "if you could take an IMAX
camera to Mount Everest or outer space, you could use it in a feature movie." In addition, Nolan
chose to edit some of the IMAX sequences using the original camera negative, which by eliminating
generation loss, raised the film resolution of those sequences up to 18 thousand lines. When the film
opened in 94 IMAX venues in 2008, all of them were sold out for the opening weekend.
A year later, director Michael Bay was inspired by IMAX's use in The Dark Knight to feature
big-screen sequences in Transformers: Revenge of the Fallen.[37] The film's co-writer Roberto Orci
suggested that the IMAX footage would be 3D, but Bay later said that considering himself an "old
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school" filmmaker, he found 3D gimmicky and added that shooting in IMAX was easier than using
stereoscopic cameras. The IMAX version of the film, in the end, contained almost ten minutes of
IMAX-filmed footage out of the two and a half hour film. Bay later partially filmed the third
Transformers film, Dark of the Moon in 3D but without IMAX. Bay returned to IMAX for the fourth
film, Age of Extinction, in 2014. It will be the first feature film to be shot using digital IMAX 3D
cameras.
Two years later, Brad Bird's Mission: Impossible – Ghost Protocol had 25 minutes of footage
shot using IMAX cameras. Bird believed that using IMAX format would bring back "a level of
showmanship" to the presentation of Hollywood films, which he believes the industry has lost due to
its emphasis on screening films in multiplexes as opposed to grand theatres, and vetoing "first runs"
in favour of wider initial releases. He also added that the IMAX format offered the viewer more
immersion than digital 3D due to its brighter, higher quality image, which is projected on a larger
screen, without the need for specialised glasses. Ghost Protocol opened on December 16, 2011, in
almost 500 IMAX venues worldwide a week before its wide release where it earned third place in the
box office and $12 million dollars.
Like with The Dark Knight, Christopher Nolan decided to film sequences of the sequel, The
Dark Knight Rises, in 15/70mm IMAX. Nolan elected not to film in 3-D and stated that he intends to
focus on improving image quality and scale using the IMAX format. In a Hollywood record, The
Dark Knight Rises featured 72 minutes of footage shot in IMAX (in comparison, The Dark Knight
contained 28 minutes.) But because of the considerable noise made by IMAX cameras, 35mm and
70mm cameras had to be used for shooting the film's dialogue scenes, and dialogue had to be dubbed
when shot with IMAX cameras. Chairman and president of the IMAX Corporation Greg Foster stated
that IMAX plans to run the film in its theatres for two months, despite only being contractually
committed to run the film for two weeks in some theatres.
J. J. Abrams' Star Trek into Darkness, Francis Lawrence's The Hunger Games: Catching Fire,
Luc Besson's Lucy, and Christopher Nolan's Interstellar are recently released films to have sequences
filmed in IMAX.
On July 9, 2014, Bad Robot (JJ Abrams Production Company) confirmed via a picture
uploaded to twitter that select scenes in Disney & Lucas film’s upcoming "Star Wars Episode VII"
would be captured with the IMAX 15/70 perf film camera, in addition to the standard 35mm film
cameras that Abrams and his cinematographer Dan Mindel have employed for shooting the movie.
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Chapter 4.
Awards for IMAX movies
In 1996 IMAX was awarded the Oscar for Scientific and Technical Achievement by the
Academy of Motion Picture Arts and Sciences. The award cited IMAX's innovations in creating and
developing a method of filming and exhibiting large-format, wide-angle motion pictures.
To date, ten native-format IMAX format films have received Academy Awards nomination,
with one winner. While on technical aspects and the usage of the IMAX system, only Wally Pfister's
cinematography on The Dark Knight has earned a nomination.
The Eruption of Mount St. Helens!, 1980 Documentary Short Subject
Fires of Kuwait, 1992 Documentary Feature
The Living Sea, 1995 Documentary Short Subject
Special Effects: Anything Can Happen, 1996 Documentary Short Subject
Cosmic Voyage, 1996 Documentary Short Subject
Amazon, 1997 Documentary Short Subject
Alaska: Spirit of the Wild, 1997 Documentary Short Subject
More, 1998 Animated Short Film
The Old Man and the Sea, Winner 1999 Animated Short Film
Dolphins, 2000 Documentary Short Subject
Chapter 5.
Other uses of IMAX
Many IMAX films have been remastered into HDTV format (cropped to fit into HDTV's 16:9
aspect ratio) for the MOJO HD, HDNet and HD Theatre networks and release on DVD and Blu-ray
Disc.
In July 2005 the BFI IMAX Cinema in London became the first to host live music concerts,
using a digital non-IMAX projector. The Science Museum London and BFI IMAX Cinema have also
hosted computer game tournaments using digital projectors. Several amusement park attractions have
integrated IMAX film segments, including back to the Future: The Ride formerly at Universal Studios
in Florida and California, Horizons, formerly at Epcot Centre and Soarin' over California at Disney
California Adventure Park and Epcot.
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Chapter 6.
Technical specifications of IMAX
6.1 IMAX (15/70)
Spherical lenses.
70 mm film, 15 perforations per frame.
Horizontal rolling loop movement, from right to left (viewed from emulsion side).
24 frames per second.
Camera aperture: 70.41 mm × 52.63 mm (2.772 in × 2.072 in).
Projection aperture: at least 2 mm (0.079 in) less than camera aperture on the vertical axis
and at least 0.41 mm (0.016 in) less on the horizontal axis.
Aspect ratio: 1.43:1.
DMR aspect ratio: 1.89:1, 2.39:1.
6.2 IMAX Dome/OMNIMAX
Fisheye lenses.
Lens optically centred 9.4 mm (0.37 in) above film horizontal centre line.
Projected elliptically on a dome screen, 20° below and 110° above perfectly centred
viewers.
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Chapter 7.
7.1 Conclusion
IMAX is an entertainment experience so real you feel it in your bones, so magical it takes you places
you have never been; so all-encompassing you’re not just peeking through the window, but part of
the action. Behind it is a world of high technology – proprietary software, architecture and equipment
pioneered by IMAX. IMAX is unique – not an entertainment or technology or distribution company
but all three at once: an innovator with patented technology; a Hollywood insider that partners with
the world’s most celebrated moviemakers to enhance their biggest blockbusters and documentaries;
and a global enterprise with more than 837 theatres in 57 countries. There’s only one IMAX, and
once experienced there’s no going back.
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7.2 Reference
http://www.google.com
http://en.wikipedia.org/wiki/IMAX
https://www.imax.com
http://en.wikipedia.org/wiki/List_of_IMAX_DMR_films
http://ieee.ca/millennium/imax/imax_birth.html
http://www.greatscience.com/visit/omnihome.php