Imax technology (venkat)

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