Ultra high-definition / 4K In
2013, Ultra high-definition TV sets and monitors started appearing, Most sources
say that ultra hi-def refers to 3840 x 2160 pixel images
and 4K refers to 4096 x 2160 pixel images. The difference depends
on the application. Either way, hi-def
displays are much sharper than regular high-definition.
We'll illustrate the difference in clarity
between SDTV and HDTV in Part Two of this module, and we'll explain surround sound and 5.1 audio in
Module 42.
It was thought that the move to digital and
the "sudden" loss of all major NTSC television stations in the U.S. would be met with
widespread viewer consternation. In fact, TV stations braced themselves for an
avalanche of unhappy viewers demanding to know what happened to their TV
stations.
This did not happen for four reasons. First, TV stations
had launched a major educational campaign about the switch that had lasted for
months, second, most viewers were receiving the stations by cable or by
satellite, which were not affected, third, for some time new TV sets had been
equipped to handle ATSC signals, and, finally, the government went so far as to
issue vouchers to help pay for set-top boxes to enable existing over-the-air
NTSC receivers to convert to over-the-air ATSC signals.
Compare
the screen enlargements shown here that represent HDTV and the standard
NTSC systems.
When projected on a 16 x 9-foot screen and
observed from normal viewing distance, the picture detail in good (1,080p) HDTV systems appears to equal
or better that attained by projected 35mm motion
picture film.
The enlarged illustrations on the left show the relative
pixel detail of SDTV and HDTV. (The illustrations assume a 40-inch TV
screen.)
SDTV produces an image with about 200,000 pixel
(picture) points. HDTV increases that by a factor of about 10 to two
million pixels.
In
the graph on the right, the taller the red bar, the sharper the
picture. Note that the interlaced (i) and
progressive (p) approaches to
scanning result in a significant difference in apparent picture
sharpness (measured in terms of discerned pixel points of detail).
All other things being equal, the difference in perceived picture sharpness centers on the
number of (visible) scanning lines, which here ranges from SDTV's 480 lines to
HDTV's 1,080 lines.
The although the 1080p system delivers the sharpest images, the
approach is so technically demanding it can only be distributed by non-broadcast
systems. However, it can be converted to film and
projected in a theater without most patrons ▲realizing they're seeing video.
We
often make comparisons between video and film quality. But video and
film are inherently different media, and the question of their relative
"quality" (a word that can mean many things to many people) has been
the
subject of lively debate. Both sides claim their medium is
superior.
When we compare film and video
media in a broadcast application, the differences between video
and film are based more on differences in their traditional production approaches than on inherent differences between the media.  |
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We discuss the relative
advantages of film and video and the differences between their quality
and costs in more detail
here.
Converting Wide-Screen Formats
Production facilities make the conversion of 16:9
HDTV/DTV images to the standard 4:3 aspect ratio in the same
way they convert wide-screen films to SDTV. (We'll
cover in-set conversion approaches later.)
Three approaches are used:
First, is when the conversion involves cutting off the sides of 16:9
image to a narrower 4:3 size. We refer to this as an edge crop or 4:3
center cut.
If we shoot the original HDTV/DTV (or wide-screen
film) with the narrower 4:3 cutoff area in mind, losing the information
at the sides of the picture should not be an issue. (This is the area on
each side of the red box in the photo below, which, as noted, is referred to as a center-cut of the full 16:9 raster.)
We refer to the procedure of
keeping essential subject matter out of the cutoff areas as shoot-and-protect.
Second, the entire production can go through a
process called pan-and-scan. In this case a
technician reviews every scene and programs a computer-controlled
imaging device to electronically pan the 4:3 window back and forth over
the larger, wide-screen format. The red arrows in this illustration suggest this panning
movement.
In the above picture, cutting off the sides would not
be an issue; but what if you had the two parrots talking (??) to each other from
the far sides of the screen?
Finally,
if the full HDTV/DTV frame contains important visual information (as in
the case of written material extending to the edges of the screen),
panning-and-scanning will not work.
In this case, a letterbox
approach can be used, as shown here.
But you can see the problem. The result is blank
areas at the top and bottom of the frame. Often, we reserve the letterbox approach
for the opening titles and closing credits of a production, and pan-and-scan
is used for the remainder.
Since some directors feel that
pan-and-scan introduces pans that are artificial and not motivated by
the action (nor the composition they originally intended). They may try to insist their work be displayed using
letterbox conversion.
Originally, producers feared that audiences would
object to the black areas at the top and bottom of the letterbox frame.
(More than one person who rented a film (video) in the letterbox format brought
it back to the video store complaining that something was wrong with
the tape.) Today, however, viewers accept this format.
There is another
way of handling the 16:9 to 4:3 aspect ratio difference -- especially
for titles and credits. You've probably seen the opening or closing of a
film on television horizontally "squeezed" in. We refer to this optical technique as anamorphic conversion.
The effect is especially noticeable when people
are part of the scene -- people who, as a result, suddenly become
rather thin. (Not that all actors would complain!) Compare the two
images above. Note how the bird in the squeezed 4:3 ratio on the right
seems to be thinner than the bird on the left.
Another way of visualizing the major SDTV-to-HDTV
and HDTV-to-SDTV conversion approaches is illustrated
here.
SDTV to HDTV In-Set Conversion Approaches
HDTV
receivers can also (roughly speaking) convert SDTV (4:3) and HDTV
(16:9) aspect ratios. Manufacturers build three options into many HDTV
receivers:
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Zoom
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Proportionally expands SDTV horizontally and vertically
to fill the 16:9 screen. This eliminates the unused blank areas we
would normally see at the edges of the picture, but it also crops
off some of the SDTV picture in the process.
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Stretch
- Expands SDTV horizontally to fill the 16:9 screen. This makes objects
a bit wider than they would normally be.
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Combined
zoom/stretch - A hybrid of the zoom and stretch modes that
minimizes the cropping effect of the zoom mode and the image distortion
of
the stretch mode.
Clearly, all these approaches
leave something to be desired, so today savvy producers originate
productions in the 16:9 wide-screen format using the "shoot-and-protect"
approach we've discussed.
Digital Cinema

In November 2000,
moviegoers saw the film Bounce in both film and high-definition
video.
Satellite facilities distributed the video
version to digitally equipped theaters, which used high-definition
video projectors. The difference between the film and video versions
was difficult for audiences to discern.
Since 2000, there have been major improvements in the video
projection process.
By 2007, the images from the best
video projectors were sharper than those of 35mm film projectors.
Film crews shot Star Wars: Attack of the
Clones -- which more than 90 theatres around the world projected
in
its digital form -- entirely on 24p video (which we covered earlier). Whereas film and processing would have
cost
several million dollars, the cost of videotape for this production was
only about $15,000.
More and more
"films" intended for theaters are being shot with high-definition video.
After elements such as special effects,
editing, and color correction are completed, a technician can convert
the final product to 35mm motion picture film, or more commonly now record it on
a hard disk for distribution to theaters.
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A major step toward video projection in theaters was taken with the release of the 3-D motion picture, Beowulf. The "film" was also seen as representing a major step forward in ▲digital animation.
Beowulf is based on a famous Old English epic poem about a warrior who fights terrorizing monsters -- designed to be all the more scary in 3-D.Despite the limited number of theaters equipped with 3-D video projectors and the fact that patrons had to wear special glasses, this film toped the box office when it was released in late 2007.
But the all-time box office record was set in late 2009 and
early 2010, when
the 3-D "film" Avatar quickly became the largest grossing film in
history. Many theaters used video projectors for this production.
Each year, the motion
picture industry spends almost a billion dollars duplicating films and
distributing them to theaters around the U.S. and the world. Films have limited
life; they collect dirt and scratches and soon must be replaced. Video can cut the billion-dollar figure to a
fraction of this amount.
This file on
digital cinema
has more information.
Plus, pirating
(creating and selling illegal copies) is a constant problem,
costing the motion picture industry billions of dollars in lost
revenue.
Pirating feature films is far more difficult when they're encrypted
and either sent directly to theaters via satellite, or, more commonly, delivered to theaters on a high-capacity disk drive. We discuss the issue of
pirating in more detail
here.
In addition to cost savings, digital
cinema offers production advantages.
We can immediately play
back and evaluate a scene we shoot in video -- even while the actors
and production personnel
are still in position. With film the hours of delay involved in processing and
preparing film "rushes" (rough prints for quick screening) make this
impossible.
Today, however, most film directors use video
assist, or shooting
on film and simultaneously viewing and recording scenes on
video. This means they can play back and evaluate their work as they go along.
Finally, not only are postproduction costs far
less with video, but visual effects are much more easily and
inexpensively produced.
The chart below indicates the excepted growth of theaters moving to some form of digital "film" projection.
Percentage of U.S. Digital Theaters
2005 |
(3%) |
2006 |
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2007 |
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2008 |
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2009 |
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2010 |
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2012 |
(72%) |
Today, most audiences can't tell the difference between professional film and video projection systems. |
Traditional "Hollywood thinking" has long opposed production with video equipment for "serious, professional work."
However, today, the cost savings for video production alone, not to mention video's many production, post-production and distribution advantages, make the move to video for both production and theater presentation inevitable.
The key differences between film and video are discussed here. |
In addition to showing feature films, theaters with digital projectors can provide
patrons with other entertainment, such as live concerts, Broadway
shows, sporting events and productions aimed at special audiences.
Digital theaters can operate with fewer
employees, representing a considerable
cost savings over time. Offsetting this savings, however, is the
initial
investment for digital projectors and the associated computer -- an
estimated $60,000 to $120,000 per theater screen
Is 3-D Production Finally
Going to Catch On?
Over
the years, three-dimensional (3-D) movies and TV programs have often tried, but
failed, to catch on with the general public. However, new technology such as
HDTV, digital video projectors, Blu-ray discs, 3-D cable networks and the
award-winning films such as the Avatar, which most people saw in 3-D,
have given 3-D at least a temporary boost.
3-D has the potential to revitalize the industry. Watching something in hi-def makes you feel like you're there; watching something in 3-D HD makes you feel like you can reach out and touch what's there 
-Phil Swann of TVPredictions.com.
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But, as of 2013, the move to 3-D TV was having a difficult time --
primarily because of a shortage of programming and the need to wear special
glasses.
The latter was eliminated as an issue when a prototype of a large-screen, 3-D TV
set was demonstrated for audiences in 2011. Unlike previous 3-D sets, no special
glasses were required and the 3-D image held up at different viewing angles. However, some viewers report problems in viewing the images, so it may be a while before 3-D television is widely accepted.
This link will take you to more
information on 3-D film and video production.
You can find information on film revenues, top
grossing films and the future of motion pictures
here.
For a more detailed look at the
various DTV and high-definition standards in the United States,
including those for digital cinema
click here.
In the next module, we'll begin discussing audio and video
equipment, starting with a key part of a video camera: the lens.
