Craig seems very confused on this subject of screen dimensions and field of
view, so I managed finally to find something informative that he can peruse, to
get the idea of what's going on. Beyond just brainless hype.
First off, there is IMAX and there is OMNIMAX. IMAX is essentially flat
screens, even if slightly curved. It's not a wrapped around screen, that cover
your full 180 degree FOV, going up the walls to the left and to the right of
the audience. (I already provided proof of this essentially 180 horizontal
degree FOV of human vision, in case Craig wants to argue that point too, in
previous links. And it's easy enough to verify this, just by raising arms to
the left and to the right.)
OMNIMAX is domed, and truly "covers your field of view," not just in the
mindless hype. But we are talking flat screens here, or essentially flat. Just
like regular IMAX does not wrap around the audience.
Here are some excerpts that Craig needs to absorb, to correct his
misunderstandings of the subject, IN PARTICULAR on the FOV offered by IMAX. Pay
attention:
http://lfexaminer.com/20090522a.htm
"Engineer and co-founder William Shaw described the essential elements of IMAX
theater design in a 1983 article in the SMPTE Journal, co-authored with J.
Creighton Douglas.
"'The high-resolution picture is used in conjunction with a large screen and
carefully organized audience seating to ensure that minimum and maximum viewing
angles lie between 60° to 120° horizontally and 40° to 80° vertically for the
farthest and nearest spectators respectively. The intent is to create an
illusion of 'being there,' rather than present a 'normal' motion picture
through a well-defined window. Most important, in our view, is to strive for
audience viewing angles that approach those encountered in reality; that is,
horizontal and vertical angles which extend well into the area of peripheral
vision and which require eye/head movement to take in the entire picture. The
feeling of a large window on reality is found to be enhanced if the screen
appears to fill the entire front of the theater, wall-to-wall and
floor-to-ceiling.'"
Then the authors checked out reality by going to various IMAX theaters:
"The maximum horizontal viewing angle from the front row of these theaters
ranges from 103° to 122°, but most are under 110°. So the seats in the front
half of these houses fall within the range of horizontal angles Shaw and
Douglas specified. But in theaters of conventional design, movie goers rarely
choose seats that far forward, most preferring to sit in the back half. The
design of a classic 0.9W IMAX theater enforced a closer seating position
relative to screen size, and thus guaranteed a more immersive experience for
all viewers.
"So far we have been dealing only with the horizontal field of view. With the
change to Hollywood's wide aspect ratios, IMAX digital and MPX theaters have
dramatically reduced the viewer's vertical field of view. For any given width,
a screen with a 1.9 ratio is 25% smaller than a 1.43 screen.
"In a classic IMAX theater with a 1.43 aspect ratio screen, the vertical field
of view from a last-row seat at 0.9W is 42.5°. (Shaw's goal was between 40° and
80°.) In a digital theater with a screen aspect ratio of 1.9, and its last row
at 1.2W, the minimum vertical angle is 25°. And this is the best case: as we
see from the examples above, most digital theaters seem to have shorter screens
and deeper houses, yielding minimum vertical angles as small as 20°."
So, Craig, unless you are disputing that human vision is roughly 90 degrees
vertical and 180 horizontal, for which you can find plenty of evidence and/or
measure this on your own, and I already provided links that explain this,
there's no way that IMAX covers your FOV. The intended range is 60 deg to 120
deg horizontal, depending where you sit, so not even close to your FOV.
As I already showed you, a 61 degree horizontal FOV is achievable in a home, at
1.5 screen height viewing distance, which can be done without changing the
furniture. Just drape that large OLED on a wall.
Craig might also check on his own, online, to see mention of motion sickness
caused by IMAX, with some material. It exists. Duh. Before arguing, best to
check facts.
Bert
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