电视台专业词汇

AB Roll Editing - Creating an edit master tape from two source VTRs on a linear editing system, one contains the A-roll, and the other the B-roll. Transitions other than cuts, such as dissolves and wipes, are possible.

Alpha Channel - Designed for creating depth in computer graphics, an alpha channel works like a key, choosing the opacity of all pixels in the image.

Assemble Editing - adding shots on videotape in a consecutive order without first recording a control track on the edit master tape.

Audio Track - the area of the videotape used for recording the audio information. Also a common term for any audio accompanying to video.

Back Light - Illumination from behind the subject and opposite the camera.

Barn Doors - Metal flaps in front of a lighting instrument. These control the spread of the light beam.

BNC (British Naval Connector) - A type of connector used on most professional video equipment providing a secure twist-lock capability.

B-Roll - Stock footage acquired for miscellaneous needs.

CG or Character Generator - an electronic device dedicated to the creation of letters, numbers and images. Its output can be directly integrated into all video images.

Charge-Coupled Device (CCD) - A device made up of semiconductors arranged in such a way that the electric charge output of one semiconductor charges an adjacent one. These are used in most digital and analog cameras today.

Chroma Key - A keying affect that uses color (usually blue or green) to indicate selected screen areas. All keyed areas are replaced by other video (like Computer Generated Imagery , Still images of backgrounds, Virtual Sets or other video).

Chrominance - The color information contained in a video signal separate from the luminance component, consisting of the hue (phase angle) and saturation (amplitude) of the color subcarrier signal. Changing the chrominance does not affect the brightness of the picture.

Close-up (CU) - Object or any part of it seen at close range and framed tightly. The close-up can be extreme (extreme or big close-up) or rather loose (medium close-up).

Color-Bars - A color standard used in video production for the alignments of cameras and videotape recordings. Color bars can be generated by most professional portable cameras. They are designed to be viewed with a vectorscope or a waveform monitor and adjusted with a Time Base Corrector.

Composite Video - A video signal in which the luminance (brightness), chrominance (color), blanking & sync pulses and color burst information have been combined rather then kept separate as in component video.

Control Track - The area of a videotape used for recording the synchronization (timing) information on an analog tape. Time Code often replaces this function on digital video tape.

Depth of Field - The area in which all objects, located at different distances from the camera, appear in focus. The depth of field depends primarily on the focal length of the lens, its f-stop, and the distance from the camera to the object.

Dolly - To move the camera toward (dolly in) or away (dolly out) the object. This is also the name of the tool which creates this effect.

Dub - The duplication of an electronic recording. The dub is always one generation away from the recording used for dubbing with the exception of digital recordings, where identical copies can be made (In analog systems, each generation shows increased deterioration from the last.)

Fade - The gradual appearance of a picture from black (fade-in) or disappearance to black (fade-out). Also changing gradually from one image to another (crossfade).

Fill Light - Additional light on the opposite side of the camera from the key light to illuminate shadow areas and thereby reduce falloff. Filling is usually done with floodlights.

Focal Length - The distance from the camera at which an object comes into focus.

Focal Plane - The space between the focal length and the farthest object in focus. Changes depending on the f-stop and may continue to infinity.

F-Stop - The calibration on the lens indicating the aperture (the opening in the lens’ iris). The larger f-stop number, the smaller the aperture; the smaller the f-stop number, the larger the aperture.

Gel - Generic name for color filter put in front of spotlights or floodlights to give the light beam a specific hue.

Generation - The number of dubs away from the original recording. A first-generation dub is struck directly from the source tape. A second-generation tape is a dub of the first generation dub (two steps away from the original tape), and so forth. The greater the number of non-digital generations, the greater the loss of quality.

Headroom - The space left between the top of the head and the upper screen edge.

Insert Editing - Produces highly stable edit. Requires the prior "laying" of a continuous control track by recording black on it.

Interruptible Feedback or Interruptible Foldback (I.F.B.) - A prompting system that allows communication with the talent while on the air. A small earpiece worn by on-the-air talent that carries program sound (including the talent's voice) or instructions from the producer or director.

Iris - Adjustable lens-opening mechanism. Also called lens diaphragm.

Jump Cut - A vertical or horizontal shift in image when using non-synchronous sources

Key Light - Principal source of illumination. Usually a spotlight.

Lavaliere - A small microphone that is clipped onto clothing. (Sometimes called a lav or a lapel mic)

Lens - Optical lens, essential for projection an optical image of the scene onto the front surface of the camera imaging device (a CCD for example). Lenses come in various fixed focal lengths or in a variable focal length (zoom lenses), and with various maximum apertures (lens opening).

Level - For Audio: sound volume. For Video: video signal strength.

Linear Editing System (LES) - Uses videotape as the recording medium and allows tape-to-tape transfer of video. On non-digital LESs the resulting master is 1 generation from the original tapes.

Live - A program broadcast from a real-time mix without an intermediary medium like videotape.

Live-to-Tape - A program mixed live, but recorded to an intermediary medium (like videotape) for post-production (like editing) or for later broadcast.

Long Shot (LS) - Object seen from far away or framed very loosely. The extreme long shot shows the object from a great distance. This is often used as an establishing shot.

Luminance - That part of a video signal relating to the degree of brightness at any given point in the video image. If luminance is high, the picture is bright and if low, the picture is dark. Changing the chrominance does not affect the brightness of the picture.

Master Control - Controls the program input, storage, and retrieval for on-the-air telecasts. Also oversees technical quality of all program material.

Medium Shot (MS) - Object seen from a medium distance. Covers any framing between a long shot and a close-up.

Mic - Short for Microphone

Mixing – For Audio: combining two or more sounds in specific proportions (volume variations) as determined by program context. For Video: Using multiple sources in composing a program for live or live-to-tape shows.

Noise - For Audio: unwanted sounds that interfere with the intentional sounds, or unwanted hisses or hums inevitably generated by the electronics in or near the audio equipment. For Video: electronic interference like that which shows up as "snow" or a waterfall like digitizing effect.

Non-Linear Editing (NLE) -

Destructive NLE - Editing like the kind found in cutting a roll of film into parts, then reassembling some or all of those parts to create a new length of film. Thus destroying the original film.

Non-Destructive NLE - Found in computer editing systems like Avid, Final Cut Pro and Premiere, This combines the “cutting and pasting” approach of film editing with the non-destructive properties of video editing, leaving an intact original copy of the footage and allowing the editor greater freedom in rearranging shots. Because of the prevalence of personal computers, this is a very popular method for editing for both amateurs, professionals and filmmakers.

NTSC - National Television Systems Committee, also the standard for Television pictures and broadcasting in the US, Canada and Japan. Over the air television in the US today (2004) is primarily of this standard.

Over the Shoulder Shot (O/S) – The camera looks over a near person's shoulder (shoulder and back of head included in shot) at another person. Often this is used in interviews, the interviewer near and the interviewee facing back.

Pan - Horizontal turning of the camera.

Pixel - a unit of digital video and digital images. While most computer monitors and media employ square pixels, NTSC video like the kind found on broadcast television uses “tall” pixels, which are of a rectangular shape.

Post-Production - Any production activity that occurs after the production but before the completion of a project.

Postproduction Editing - The assembly of recorded material and affects editing after the end of actual production.

Pre-Production - Preparation of all production details.

Preroll - To start a videotape and let it roll for a few second before it is put in the playback or record mode in order to give the electronic system time to stabilize. Often necessary for analog devices.

Preview Monitor - This monitor shows the next input the director has readied in a live or live-to-tape program.

Producer – The creator and organizer of programs.

Production - The actual activities in which an event is recorded and/or televised.

Shotgun Microphone - A highly directional (unidirectional) mic with a shotgun like barrel for picking up sounds over a great distance or only from a particular direction. This is most often preferred in situations were outside noise can not be eliminated.

Source - The device that supplies the various program segments to a VTR, Editor or Mixer.

Super - Short for superimposition. the simultaneous overlay of two pictures on the same screen. Good examples are Alpha or Keying in an object into a background (see Alpha Channel and Chroma Keying), Titles and Graphics.

Switcher - Used for live editing, this device allows a technical director to switch between a number of sources of video and audio in a live or live-to-tape program environment.

Synchronization - A series of measures that allow an outfit, such as a TV station or a production studio to synchronize all sources so that all frames start at the same instant.  

Take - A singular section of video which when put together with others makes a program.

Talent - Collective name for all performers and actors who appear on a program.

Tally Light - A light on the camera which indicates that the camera is live to the switcher.

Teleprompter - A device that projects moving copy in front of or near the lens of the camera so that the talent can read it without losing eye contact with the viewer.

Tilt - To point the camera up or down.

Time Base Corrector - A device commonly used to synchronize video and adjust color balancing.

Time Code - Found on most digital video formats, it stores frame-accurate timing information on the tape.

Tripod - A three-legged camera mount.

Two-Shot - Framing of two people in a single shot.

Unidirectional - The microphone can hear best from the front. (A shotgun mic is a good example)

Vectorscope - Designed to test color, the output from this device allows the user, in conjunction with color bars, to adjust video levels so that all cameras used have even video baseline.

Video Track - The area of the videotape used for recording the video information. Also a common name for all video used.

Virtual Set - Used with chroma keying, this technique uses a number of devices to create a virtual reality around the real world items/characters on the virtual set. Many news stations use virtual sets instead of real ones because it is a cost saving option.

Viewfinder - A small video monitor on a camera that displays the picture the camera generates.

VU Meter - A volume-unit meter; measures volume units, the relative loudness of amplified sound. The measurements are either arbitrary or in decibels (dB)

Waveform Monitor - An oscilloscope which is designed to monitor composite video and sync signals. (see Synchronization)

White Balance - The adjustments of the color circuits in the camera to produce a white color in lighting of various color temperatures creating the proper relative shading of white so it is neither too blue or too red.

Wipe - A transition in which one image seems to "wipe" off (replace) the other from the screen.

Wireless Microphone - A system that sends audio signals over the air, rather than through microphone cables. The mic is attached to a transmitter and the signals are received by a receiver connected to the audio console or recording device.