T356 2015 - Week 13
- DTV Signal / Distribution
- Telecines & the 3-2 pulldown
- Review Budget/Remote Exercise - Questions? This is due next week.
- PSAs must be turned in this week. Only about half have sent links and provided critiques & emails.
- Final Project materials are due THIS WEEK. You have until Friday. This is a group-graded part of the assignment. I'll give you time today to meet in your Final Project groups
- Please email Jim this week if you want an extra credit opportunity. These must be arranged in the next week or two. (Not during the last two weeks of class.)
- Due to popular demand, the Spring 2015 T356 FINAL EXAM will be held Monday, May 4 at 12:20 PM in Studio 5.
Review ratings & shares for quiz
Field Production & Big Remotes /
Sports Remotes - Crews can be very large - more than 100 people are
needed for a major sports event.
Check out the floor plans for the various events in the Zettl book.
Always remember a solid establishing shot and adhering to the 180 degree
rule. Mics that have to pick up sound from a long distance are typically
shotgun and/or parabolic.
Be prepared to make/complete
a location sketch for a major event. You will have to decide where
to place the cameras and microphones and
explain your reasoning.
Remote operations depend heavily
on reliable communication devices. Producers often distribute cell phones
to production team leaders.
- ENG: cell phones, scanners, pagers
- EFP: small productions (single camera)
you can just talk to the cameraman’s
ear. Walkie talkies, phones
- Big Remotes: PL private line, IFB, intercom
IFB - Interruptible feedback or foldback (British term used to describe
headphone feeds). Usually an earpiece worn by the talent so that they
can receive instructions/information by the director.
Signal transport & delivery
Programming can be delivered in three ways:
- Terrestrial broadcast
- Satellite (E.g. Direct TV)
- Wired/cable (E.g. ATT, Comcast)
Most programming is delivered in some form of MPEG.
Terrestrial broadcasting uses the electromagnetic spectrum. The FCC was originally tasked with overseeing the broadcast spectrum, which is used by television, radio, the military, cell phone companies, and even your garage door openers.
Digital Television (DTV) - The analog
cutoff date was Feb 19, 2009. DTV does not necessarily mean HDTV. Broadcasters can deliver standard resolution TV (SDTV) over DTV equipment.
You can squeeze 4 SD programs in the same space used to broadcast one HD program. If you live in the right place (with good reception) you can receive a number of DTV network channels free via your TV tuner. (Around here you can only get WTIU.)
- 1080 i and p (24, 30 & 60 fps. 16 x 9) 1920 x 1080
- 720 i and p (24, 30 & 60 fps. 16 x 9) 1280 x 720
- 480 i and p (24, 30 & 60 fps. Both 16 x 9 and 4 x 3)
(i = interlaced, p = progressive)
Satellite Systems - All geosynchronous communication satellites orbit the earth above the equator 22,236 miles / 35,786 km above the earth).
In other words all of the downlink satellite dishes you see are
pointed towards the south (somewhere over the equator).
Satellites used for broadcast
are either C or KU band. KU band dishes can be smaller (2 feet). Direct
satellites or DBS (such as DISH or DirectTV) operate on the KU band.
- Uplinks (send to satellite)
- Downlink (receive)
Transponder - a combination receiver/transmitter found in the communication
Microwave transmission - Power & size varies.
Very small, focused signal. Don’t stand in front of one! Can go
from camera to truck, truck to relay station, truck to satellite, or directly to the station.
Wired/Cable-based systems - Twisted pair, Coaxial & fiber-optic.
Compared to cable or fiber-optic, twisted pair (E.g. traditional phone line) is capable of carrying the least amount of information. Most cable companies started out with coaxial cable. Most now are using fiber-optic, which is capable of carrying more information.
- Headend - origination point/control center of the cable system.
- Trunk-line- primary distribution (fiber-optic
- Feeder lines- secondary distribution (through blocks/neighborhoods, etc)
lines- cables to homes or businesses
- Multicast - delivery of information to a multiple destinations simultaneously
- VOD - Video On Demand
- SDV - Switched Digital Video - A method of broadcasting only channels that are currently tuned, rather than every channel offered at once.
Convergence - These have been interesting times, as cable companies are now offering phone service and phone companies are offering TV.
Many consumers are giving up monthly channel contracts as more and more TV programming is accessible via the Internet. It's possible to get a great deal of free programming over broadband. Usually the free content is interspersed with commercials. (Sound familiar?) Easy to use set top boxes and even game consoles provide a way to stream content directly to your TV, bypassing the cable or satellite tuner.
More and more devices are making it easier to stream content to your TV set without a cable or satellite tuner.
World TV Standards & Digital TV
World analog TV platforms:
- NTSC - 525 lines at 30 frames (60 fields) 4x3 aspect ratio
- PAL - 625 lines at 25 frames (50 fields) 4x3 aspect ratio
- SECAM - same as PAL, just incompatible
NTSC (National Television Systems Committee) definition
of standard definition TV, (used in North America, some of South America,
Japan, etc) uses a frame rate close to 30, roughly 29.97 frames per second.
There are 525 scan lines; approximately 480 of these are visible. The
HD (high definition) standard for broadcast has been created by the ATSC,
the Advanced Television Systems Committee, which was formed at the urging
of the FCC to establish standards for the new high definition formats.
PAL (Phase Alternate Line) is used in most of Europe,
Australia, & Asia and runs at 25 frames per second using 625 lines.
SECAM (Sequential Color and Memory)
Here in the US, the NTSC analog standards are still being used by legacy gear. However all of the new digital broadcasting and distribution follow the ATSC guidelines.
ATSC - A number of industry associations, corporations, and educational institutions formed the Advanced Television Systems Committee (ATSC) in 1982. The ATSC is a not-for-profit organization that develops voluntary standards for advanced television systems (www.atsc.org). Such advanced systems include enhanced analog TV, digital TV (DTV), standard definition TV, high-definition TV, and data services. The ATSC’s published broadcast standards are voluntary unless adopted and mandated by the FCC.
In December 1996, the FCC adopted most of the standards proposed by the ATSC, mandating that broadcasters begin broadcasting digitally.
Converting 24p video & film to interlaced 60i video
When converting film or 24p video to 30/60i (29.97) video we use a 3:2
Film runs at 24 frames per second.
24p refers to video shot at 24 frames per second progressive- that means
there are no fields.
Since film runs at 24 fps and video runs about 30 interlaced fps, the two aren't
directly interchangeable at least on a frame for frame basis. (To be
more precise, 23.976 film frames become 29.97 video frames.) In order
to transfer film to 30 fps video, the film frames must be precisely sequenced
into a combination of video frames and fields.
A telecine is a piece of hardware containing a film
projector sequenced with a video capture system. The telecine process
is a term used to describe the process of converting film to video, also
called a 3 2 pulldown. In the 3-2 pulldown each frame of film gets converted
to 2 or 3 fields of video.
Note how four (24p fps) frames are converted to five interlaced frames (30i fps).
The problem with converting film frames to fields, is that some video
frames have fields from two different film frames. If you think about
it you'll see that this can present all types of problems.
Terms & abbreviations you should know:
- Big Remote
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