Those 70mm IMAX spools of film are huge. You'll need 2 of those if shown in 3D (one for each eye). :awe:
Yeah, the dome down here at MOSI is pretty wild too, have only been over to it a few times.
Movies not formatted especially for the sphere can look a bit odd sometimes, but is pretty awesome setup. I think they have even corrected for that these days though.
http://www.mosi.org/imax-dome/about-dome-screen.aspx
Not driving over today, have a regular IMAX near me but looked and the doe has it on and think will make the drive through the Tampa traffic to see it there next Saturday.
23 miles isn't bad.
Surprised aren't any pics of the projection room online from there, it's all glass fronted and many might not even go look, it's an awesome setup.
Yeah, the film spools are horizontal and look like stock feeders on progressive die setups, and the bulb used for the projector is the same The Cape uses for lighting up the gantries on night launches I believe.
"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.
[12]
Projectors
The 15 kW
Xenon short-arc lamp used in 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 (6 ft) tall and 195 cm (6 ft) long.
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.
[13] 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."
