Actuality event Any event that is not specifically staged for television that exists in its own time scale.
A/D conversion Converting an analogue signal into a digital signal.
Ad-lib shooting Impromptu and unrehearsed camera coverage.
Alarm control Control of audible warning through speaker of camera/recorder of a fault condition in camera or VTR fault.
Aliasing Incorrect sampling due to input frequencies exceeding one half of the sampling rate.
Amplitude Maximum height of a waveform or signal.
Analogue signal A varying voltage signal.
Angle of view The horizontal angle of view of a specific focal length lens. Angle of view varies with a zoom lens.
ASA American Standards Association. A method of rating the speed of film. Replaced by International Standards Organisation, ISO, or Exposure Index, EI.
As-directed Unrehearsed camera coverage controlled at any moment by the director.
Aspect ratio The proportion of the picture width to its height.
Assembly edit Recording process where the video, audio and timecode are recorded, in sequence, to a blank tape.
Attenuation Reduction of signal level.
Auto-gain An electronic circuit which automatically adjusts audio recording level to keep within prescribed limits.
Auto-iris Automatic adjustment of the iris depending on main subject luminance.
Azimuth The azimuth on an audio tape machine is correct when the record head is at a right angle to the tape.
Back focus See Flange back.
Backlight Lamp used to separate subject from the background by rim lighting the subject from upstage.
Balance The relative level between sound sources or light sources.
Balanced line Connection of audio signals where the two signal paths are kept separate from earth.
Bandwidth The range of frequencies required for successful transmission of audio (20 kHz) or television (PAL 5.5 MHz).
Barndoors Hinged metal flaps on the front of a lamp used to control the spread of light.
Bars See Colour bars.
Bass Lower end of the frequency spectrum.
Battery lamp Small battery-powered lamp often mounted on top of the camera.
Betacam format 12.5 mm tape cassette video format recording, on two adjacent video heads, the luminance signal (Y) and a chroma signal consisting of a compressed time division multiplex of the colour difference signals (R – Y and B – Y).
Bias High-frequency signal added to the audio during the magnetic recording process.
Big close-up (BCU) A description of the size of a shot. When applied to the face, the frame only includes the point of the chin to mid-forehead.
Bit A unit of binary code.
Bitstream A series of binary digits.
Black balance Automatic adjustment of the black level of the camera.
Black level The amplitude of the television video signal representing the darkest past of the picture.
Black wrap Black anodized aluminium foil used to control spill light or shaping a light beam.
Blonde A 2000 W portable lamp.
BNC A twist-lock cable connector often used on monitor video cables.
Bouncing A method of transferring audio from one track to another. Also a method of obtaining a soft light source from a hard source.
Breaker button Automatic cut-out of power supply to electronic equipment if overload is detected.
Brightness A term often incorrectly used to mean luminance. Brightness is a subjective effect; it is how bright we see an object.
C-mount Standard broadcast video lens mount.
C10 rate A slow charge of constant current equal to 1/10th of the ampere-hour rating of the battery. A safe extended charge rate that will not produce a build up of oxygen.
Camera angle The position of the camera relative to the main subject in the shot.
Camera left Left of frame as opposed to the artiste’s left when facing camera.
Camera right Right of frame as opposed to the artiste’s right when facing camera.
Camera sensitivity Quoted in relation to a subject with peak white sensitivity, scene illuminance (lux), f number of lens and signal-to-noise ratio for a stated signal.
Candela The unit of measurement of the luminous intensity of a lamp.
Canting the camera Angling the camera so that the horizon is not parallel to the bottom of the frame.
Caption generator Electronic equipment that allows text to be created and manipulated on screen via a keyboard.
CCD A charge-coupled device; it converts light into electrical impulses which are compiled into the TV picture format.
Chroma Another name for saturation, a control usually found on monitors.
Chroma key An electronic process for inserting an artiste (foreground) into a background picture; also known as colour separation overlay (CSO) in the BBC.
Clean feed An audio source providing a programme participant with all audio signals but excluding own audio contribution.
Close-up (CU) Shot size. When applied to the face, the top of the frame rests on the top of the head and the bottom of the frame cuts at the position of a knotted tie if worn.
Coaxial cable Cable with a central conductor surrounded by a sheath of screening.
Coincident pair Two microphones that are effectively in the same position.
Coloration Unpleasant effect where sound is repeated with a small time delay. This may occur where two microphones pick up the same sound.
Colour balance See White balance.
Colour bars A special test signal used in colour television.
Colour temperature A convenient way to describe the colour of a light source by relating it to a black body radiator, e.g. heated poker, measured in Kelvins (K) after Lord Kelvin (physicist).
Component The individual or difference signals from the red, blue and green channels and luminance signal.
Composite The colour signals encoded (combined) with the luminance signal. Also, old definition for luminance signal plus synchronizing pulses.
Compression The process of reducing the amount of signal data that is required to be passed through a finite channel whilst endeavouring to maintain the quality of the originating signal. Also a method of reducing the range of audio levels.
Condenser A type of microphone using charged plates to transfer sound pressure changes into electrical signals.
Contrast ratio The ratio between the brightest part of the subject and the darkest part.
Control track A regular pulse recorded on video tape to identify the position of the video signal and tape speed.
Cosine law A law which follows the cosine 0°–90°.
Crash zoom Either an intentionally maximum speed zoom or an ‘emergency’ fast zoom to recompose ‘on-shot’.
Crossing the line Moving the camera to the opposite side of an imaginary line drawn between two or more subjects after recording a shot of one of the subjects. This results in intercut faces looking out of the same side of frame and the impression that they are not in conversation with each other.
Cross talk Unwanted signal picked up between adjacent signal cables or from one audio track to another.
CSO Colour separation overlay – see Chroma key.
CTDM Compressed time division multiplexed chrominance recording; part of the Betacam method of recording.
Cue A particular lighting condition or an indication for action to start, i.e. actor to start performing or lighting change to start.
Cursor A vertical or horizontal line that can be positioned by the cameraman in the viewfinder as a reminder of a precise frame position or to check a vertical or horizontal visual element.
Cutaway Cutting away from the main subject or master shot to a related shot.
DAT Digital audio tape.
DCC Dynamic contrast control compresses highlights of the picture to allow a greater contrast range to be recorded.
Decibels (dB) A logarithmic ratio of changes in sound intensity similar to the ear’s logarithmic response to changes in sound intensity.
Depth of field The zone of acceptable focus in the field of view.
Dichroic filter A mixture of glass layers with different refractive indices, designed to reflect one colour whilst allowing others to pass through. Commonly used on battery lamps to convert the colour temperature of tungsten to daylight, and in light splitting blocks.
Diffuser Material which scatters the light to create a softer light source.
Digital A data stream of individual binary numbers representing an unbroken variable value.
Digital injection (DI) A method of directly connecting an audio output from a musical instrument or other audio equipment to a balance audio input.
Digital manipulation Rearranging and recombining small elements (pixels) of an image.
Dimmer An electronic device for controlling the light output from a light source. Usually a thyristor or silicon controller rectifier (SCR) but recent developments have included the transistor dimmer.
Dingle Branches placed in front of a luminaire to create a dapple effect or in front of a lens to create a foreground feature.
Discharge light source Lamps which produce light by ionizing a gas contained in a bulb.
Display mode Selecting particular information about the camera to be displayed in the viewfinder.
Distortion Unwanted damage to an analogue signal that results in the output of a system being different from the original.
Dolby A noise reduction process used in audio recording and playback.
Downlink The signal path between satellite and receiver.
Down stage Moving towards the camera or audience.
Dropout The short loss of a recorded signal due to faulty head-to-tape contact or tape imperfections.
Dry Describes the inability of a performer either to remember or to continue with their presentation.
Dynamic range The relationship of the highest value to the lowest value of sound intensity or picture brightness that can be reproduced.
EBU European Broadcasting Union. Advisory and regulatory body for broadcasting in Europe.
Edited master The final version of edited material that will be seen by the viewer.
EDL Edit decision list created to define the in and out points of an edit sequence.
E-E Electronics to electronics; a VTR facility switch which enables the signal to bypass the recording head.
Effects (Fx) Visual or audio effects.
EFP Electronic field production is the term used to describe single camera location video programme making other than news.
Electronic shutter An electronic method of varying the length of exposure time of the CCD. Can be used to improve the slow motion reproduction of motion.
Encode The technique of combining colour information with a luminance (monochrome) signal.
ENG Electronic news gathering describes the single camera video recording of news events.
Entropy The unpredictable part of a signal which has to be transmitted by a compression system if quality is not to be lost.
Equalization Increase or decrease in the level of chosen audio frequencies.
Establishing shot The master shot which gives the maximum information about the subject.
EVDS Enhanced vertical definition system; a method of reducing motion blur.
Extender An additional lens which can be switched internally in the zoom lens to extend the zoom range of focal lengths.
Eyeline The direction the subject is looking in the frame.
f number A method of indicating how much light is being allowed to pass through the aperture of the lens.
Face tones Signal derived from face tones, typically (average European face) about 0.5 V.
Fader A control for varying the level of an audio or video signal.
Feed Either a video signal or the cable that carries the signal.
Field One top-to-bottom scanning of an image. Two fields interlaced make up one frame.
Field integration A technique connected with the read-out of a CCD where adjacent lines are averaged.
Fill light A light source used to make shadows transparent, i.e. reduce the contrast.
Filter wheels Filter holders of colour correction, neutral density or effects filters that are arranged within the camera to allow for the quick selection, by rotating the wheel, of the required filter combination.
First generation The acquisition medium on which the video signal was first recorded.
Flange back The distance from the flange surface of the lens mount to the image plane of the pick-up sensor commonly known as the back focus.
Flight kit A portable set of location lamps and stands able to be packed in a compact container for easy transportation.
Focal length of a compound lens The distance from the principal point of a compound lens (e.g. a zoom lens) to the point at which rays from an object at infinity form the most sharply defined image.
Focus pull Moving the zone of sharpest focus to another subject.
Foldback A feed to allow artists to hear selected sound sources on loudspeakers or headphones.
Foot candle Unit of illuminance in imperial units, 1 lumen/ft2 = 1 foot candle.
Format The method of recording the image (e.g. DVCPro; S-VHS; Betacam, etc.).
Frame One complete television picture comprising of two interlaced fields or a single film image.
Frame integration A technique connected with the read-out of a CCD where vertical resolution is improved at the expense of motion blur.
Frame interline transfer (FIT) A method of transferring the CCD charge to eliminate vertical smear.
Frame store An electronic device for storing individual video frames.
Frame transfer (FT) The method of transferring the charge vertically from the CCD pixels exposed to the subject, to a duplicate set of pixels.
Free run Frame identification by timecode which is set to the actual time of day when the frame was recorded.
Frequency The number of complete cycles per second.
Frequency response The range of frequencies that a particular system can reproduce without distortion.
Fresnel Stepped lens used in the fresnel spotlight.
Fundamental The original or lowest frequency of a complex signal.
Gain The amplification of a video or audio signal calibrated in dBs (e.g. +6 dB of video gain is the equivalent of opening the lens iris by 1 stop).
Gaffer The chief lighting electrician.
Gamma The law of the transfer characteristic of a system, i.e. relationship between input and output signals.
GEO Geosynchronous orbit satellite that revolves at the same rotational speed as the earth and appears stationary from the earth’s surface.
Gobo Stainless steel stencil used in profile projectors to create effects, e.g. windows, abstract pattern, moon, etc.
Grads An abbreviation of graduated applied to front-of-lens filters which progressively filter or colour the picture vertically.
Graticule Engraved calibration scale on the front of waveform monitors and vectorscopes.
Grid area The structure above a studio floor.
Grip Supporting equipment for lighting or camera equipment. Also the name of the technicians responsible for handling grip equipment, e.g. camera trucks and dollies.
GV General view; this is a long shot of the subject.
HAD Hole accumulated diode is a CCD sensor which increases the proportion of the sensor that can collect light without decreasing resolution.
Hand-held Operating a portable camera without a camera mounting.
Hard light Any light source that casts a well-defined shadow.
Harmonic A range of frequencies that are multiples of the fundamental that make up a complex waveform.
Hertz Unit of frequency, 1 Hertz = 1 cycle/second.
High angle Any lens height above eye height.
High key Picture with predominance of light tones and thin shadows.
HMI A discharge lamp producing light by ionizing a gas contained in the bulb.
Hot head A remotely controlled camera pan/tilt head often on the end of a jib arm.
Hue The dominant wavelength, colour describing what we see, e.g. red.
Hyper HAD Increasing the sensitivity of the HAD CCD by the use of a micro lens with each pixel.
Illuminance (illumination) (E) A unit of light measurement for incident light, lumens/m2 = lux.
Image size The image formed by the lens on the face of the CCD.
Insert edit The adding of video, audio or timecode, out of sequence, to a pre-recorded tape.
Insert point An input/output in a system allowing the connection of other equipment.
Interlace A method of scanning separate parts of an image in two passes (fields) in order to reduce the bandwidth required for transmission.
Interline transfer (IT) A method of transferring a charge from the pixels exposed to the subject to an adjacent duplicate set of pixels.
Inverse square law A fundamental law in lighting and sound where the intensity of light and sound falls off as the inverse of the distance squared.
Invisible technique Production method which emphasizes the content of the shot rather than the production technique.
Iris Variable circular aperture in the camera used to control exposure, calculated in f stops.
ISDN Integrated Services Digital Network is a system that allows the transfer of audio or other data via a telephone line.
Isoed Recording the (isolated) output of an individual camera or cameras in a multi-camera shoot in addition to the main recording.
JPEG The Joint Photographic Experts Group, which identifies a standard for the data compression of still pictures.
Kelvin (K) A unit measurement of heat used to describe colour temperature.
Key Mood of a picture, i.e. high key/low key.
Key Keying signal for chroma key operations.
Keylight or key The main source of light illuminating the subject.
Kicker Light used at eye level from upstage, at eye level to ‘kick’ the side of the artiste’s head.
Knee Modified part of the transfer characteristic of a camera designed to progressively compress highlights.
Ku-band The frequency spectrum between 10.7 GHz and 18 GHz.
LCD Liquid display crystal. A reflective or transmissive alphanumeric display.
Level The volume of an audio or video signal.
Line level A reference audio level measured at 1000 Hz.
Linear matrix Involves cross-coupling between R, G and B to help obtain the desirable analysis characteristics essential for faithful colour reproduction.
Live The transmission of an event as it takes place.
Locked-off Applying the locks on a pan and tilt head to ensure that the camera setting remains in a preselected position. Can also be applied to an unmanned camera.
Long lens A lens with a large focal length or using a zoom at or near its narrowest angle of view.
Long shot (LS) A description of a shot when the full length human figure fills the frame.
Look angle The angle of elevation of the signal path above the horizon to a satellite.
Low angle A lens height below eye height.
Low key Picture with a predominance of dark tones and strong shadows.
LTC Longitudinal timecode is recorded with a fixed head on a designated track on the tape.
Lumen Unit of quantity of light flow per second, ‘weighted’ by the photopic curve.
Luminaire Name given for a complete lighting unit, i.e. light source or lamp plus its casing.
Luminance (L) A measure of the light reflected from a surface. A total flux reflected of 1 lumen/m2 has a luminance of 1 Apostilb (Imperial measurement 1 lumen/ft2 = 1 foot lambert).
Luminance signal That part of the video signal which represents the relative brightness points of an image.
Luminous intensity A measure of a lamp’s ability to radiate light, measured in candelas (old term, candlepower).
Lux A unit for illuminance, 1 lumen/m2 = 1 lux.
Macro A switchable facility on a lens that allows focusing on an object placed closer to the lens than the normal minimum object distance (see MOD).
Matrix Electrical circuit for deriving ‘mixtures’ of signals, e.g. colour difference signals and luminance signals from RGB signals.
Matte box A filter holder and bellows extension for the control of flare, fitted to the front of the lens.
Medium close-up (MCU) A shot description usually describing a
framing of a person with the bottom of the frame cutting where a suit breast pocket would normally be.
Medium shot (MS) A description of shot size with the bottom of the frame cutting at the waist when applied to the human figure.
Megahertz (MHz) One million cycles per second.
Metal particle A video tape coating allowing a wider frequency response to be recorded and an improved signal-to-noise ratio compared to oxide tape coating.
Millisecond One thousandth of a second.
Mired Micro reciprocal degree value allows the relationship between a correction filter and the colour temperature shift to be calculated.
MOD Minimum object distance; the closest distance a subject in acceptable focus can be to the lens.
Modelling The action of light revealing contour and texture of a subject.
Monitor termination A switchable electronic ‘load’ (usually 75 Ω) on the back of a monitor inserted at the end of a video cable feed to prevent the signal ‘bouncing back’. If several monitors are looped together, termination only occurs at the last monitor.
Monochrome Reproduction of a single colour such as a black and white image.
Movement blur The degradation of the image related to the speed of subject movement during the exposure time of a single picture.
MPEG2 Moving Picture Experts Group 2 is a series of benchmark values specifying different degrees of compression.
Multi-generation Numerous re-recordings of the original recording.
Neutral density filter A filter which reduces the amount of light transmitted without altering the colour temperature.
Ni-Cad Nickel-cadmium is the constituent of rechargeable batteries widely used to power broadcast camcorders and cameras.
Noddies Television jargon for cutaway shots recorded for editing purposes after an interview showing the interviewer listening and ‘nodding’ at the interviewee’s comments.
Noise reduction A method of reducing the noise on recorded or transmitted analogue audio.
NTSC National Television System Committee. Usually signifies an American method of encoding colour.
OB Abbreviation for outside broadcast. Usually a multi-camera production from a non-studio venue using a mobile control room.
Off-line editing Low-quality images that are used to produce edit lists or a non-transmittable edited guide tape.
Off-shot Describes the camera when its output is not selected at the vision mixing panel to be fed ‘to line’.
On-line editing Any system that produces a final edited broadcast quality programme.
On-shot Describes the camera when its output is selected at the vision mixing panel to be fed ‘to line’.
Opacity The reciprocal of transmission of light through a film or filter.
Oscillator Equipment to produce pure tone (sine wave) used for lining-up and calibrating systems.
Oscilloscope Cathode ray oscilloscope used to provide a visual display of video signals.
Oxide tape Tape coating used in the first generation of the beta format cameras.
Pad A circuit used to reduce or attenuate the signal level.
PAL Phase alternating Line. A European development of the American NTSC system of encoding colour.
Pan-pot Pan(oramic) pot(entiometer); this adjusts the apparent position of a sound source in a stereo image.
Peak programme meter (PPM) This measures sound by averaging the peaks of intensity over a specified period and rapidly responds to high level transients.
Peak white Either 100 per cent video signal level or 60 per cent reflectance neutral grey surface.
Peak white clipper A ‘gain limiting’ circuit set to the same level in each colour channel of the camera that restricts any signal to a maximum level.
Perspective The apparent position of closeness of sound in an image. Also the optical methods used to assess or construct image depth.
Phantom power The DC supply to some types of condenser microphone using the signal cable.
Phase A time delay between two signals. It is expressed in degrees as the actual time will vary with frequency.
Picture monitor Good quality viewing monitor, similar to a receiver but without RF and sound sections.
Pink noise A random signal that appears to the human ear to contain an equal level of frequencies.
Pistol grip Hand grip controlling zoom movement that may be attached to a lightweight lens when operating the camera ‘hand-held’ or attached to a pan bar.
Pixel Abbreviation for picture cell – a single point in an electronic image.
Playback Replaying a recorded shot or sequence of shots or audio.
Point-of-view shot A shot from a lens position that seeks to duplicate the viewpoint of a subject depicted on screen.
Polecat Adjustable spring loaded aluminium tubes with rubber feet that can be used vertically or horizontally to support lightweight luminaires.
Post production Editing and other work carried on pre-recorded material.
Practical An in-shot light source, e.g. wall light. Prime lens A fixed focal length lens.
Print-through The transfer of magnetic information from one layer of tape to another when stored on a reel.
Production control rooms Production areas on outside broadcasts (see Scanner), or adjacent to studios used by production staff, lighting and audio.
Prompters A coated piece of glass positioned in front of the lens to reflect text displayed on a TV monitor below the lens.
PSC The production method of recording material on a portable single video camera.
Pulse coded modulated (PCM) Digital transmission system.
Purity In a monitor, the ability of the red gun only to hit red phosphors, etc.
Quantize In a digital system, allocation of ‘sample’ level prior to coding.
Real time (1) Timecode which changes in step with the actual time of day.
Real time (2) The actual running time of an event as opposed to ‘screen time’ – the compression of time achievable by editing.
Recces The inspection of a location by production staff to assess the practicalities involved in its use as a setting for a programme or programme insert.
Record run Timecode which increases only when a recording is made. Record run only records a frame identification when the camera is recording.
Recorded-as-live A continuous recording with no recording breaks.
Redhead A 800 W portable lightweight lamp.
Redundancy When compressing a signal, the part which can be predicted from the signal already received and therefore need not be sent. It is redundant.
Reflector Any white or silvered surface that can be used to reflect a light source.
Reverberation The gradual decay of reflected sound.
Reverse angle When applied to a standard two person interview, a camera repositioned 180° to the immediate shot being recorded to provide a complementary shot of the opposite subject.
Robotic camera A camera with a remotely controlled camera head, e.g. pan/tilt, zoom and focus. May also include camera position and height.
Rocking focus Moving the focus zone in front of and behind the selected subject in order to determine sharpest focus.
Sampling rate The number of measurement points over time that describes a continuously variable voltage.
Saturation A measure of the purity of a colour, e.g. pale red or deep red.
Scanner The production control rooms of an outside broadcast production.
Scene file A removable data storage chip from the camera that contains memorized settings.
SECAM (Sequential Couleur à Memoire) A French developed method of encoding colour.
Shooting off Including in the shot more than the planned setting or scenery.
Shot number A number assigned to a specific shot as detailed in a camera script or camera rehearsal.
Shuttling Rapidly reviewing video tape to determine content or edit point.
Signal to noise The level difference, in dB, between the wanted signal and the unwanted background system noise.
Simple PAL Monitor mode which enables the eye to average out colour errors, i.e. no delay line used. Also enables phase errors to be seen.
Single shot technique The single camera discontinuous recording of a number of shots that are later edited in post-production.
Slo-mo replay Replaying a pre-recording at a slower speed than normal transmission.
SNG (satellite news gathering) The technique of relaying video location news reports or news material via a satellite to a base station.
SOC (satellite operation centre) The control centre of the owner/operator of a satellite.
Soft light A light source that produces a soft-edged shadow.
S/PDIF A consumer version of the AES/EBU digital interface.
SPL Sound pressure level expressed in dB where the reference is the threshold of human hearing.
Spot effects Sounds that relate to short actions, usually in vision.
Star quad A four core sound cable designed to reduce unwanted interference pick-up.
Stereo Usually understood to mean a system of reproducing a wide sound image using two channels.
Stop Either the f number the lens is set to or the unit change between two standard f numbers.
Switcher See Vision mixer. Note that job titles vary from country to country.
T number Indicates the amount of light transmitted by a lens at a specific iris setting. Unlike f numbers, identical T numbers on lenses will transmit the same amount of light independent of lens design.
T piece Small BNC connectors to allow teeing of video connectors, e.g. connect two video cables to one video socket.
Talkback Inter-communication by microphone and headset between a television control room and other operational areas and technicians.
Termination 75 Ω resistor included across the video cable at the end of a transmission chain. Inclusion of 75 Ω termination ensures no reflection of energy, and ensures the signal level is correct.
The narrow end of the lens The longest focal length of the zoom that can be selected.
Tight lens A long focal length primary lens or zoom lens setting.
Timecode Enables every recorded frame of video to be numbered.
Transformer A device made with two coils wound around a magnetizable core to isolate a signal or to change its voltage.
Transient A fast changing signal.
Transient response The ability of equipment to follow fast changes in level.
Translucent Semi-transparent; usually some form of light diffuser.
Tungsten The filament material in a lamp producing light by heat.
Turtle Very low lighting stand for rigging luminaires at floor level.
Tweak Term used for small adjustments to lighting rig or operational settings, e.g. black level or iris setting.
Tx Abbreviation for transmission.
Uplink The signal path from an earth station to a satellite.
Upstage Moving further away from the camera or audience.
User-bit A programmable identification code compiled by the ‘user’ of the camera which is recorded as part of the timecode on each video frame. User-bit allows up to nine numbers and an A to F code to be programmed into the code word which is recorded on every frame.
VCA Voltage controlled amplifier.
Vectorscope Special oscilloscope designed to display the chrominance information in an easily recognizable way, i.e. hue and saturation.
Video barrel A small in-line adaptor designed to connect two BNC video cables together.
Video contrast range The relationship between the brightest part of the scene and the darkest part.
Video wall A number of individual TV screens often stacked in a rectangle displaying multiple, individual or composite images.
Vignette The shading of the edges of the picture area.
Virtual reality System of chroma key where the background is computer generated. The size and positioning of the background is controlled by the foreground camera movements.
Vision control The person who adjusts camera exposure, colour, gamma, etc., in a multi-camera production. Also applied to the area where they perform this function.
Vision mixer The person who switches between video sources. Also applied to the equipment they use to perform this function.
VITC (vertical interval timecode) These are timecode numbers recorded in one or more of the unused lines in the TV signal and can be read when the tape is in still frame.
Voice-over A commentary mixed with effects or music as part of a sound track.
Vox pops (vox populi) The voice of the people, usually consists of a series of impromptu interviews recorded in the street with members of the public.
VTR Video tape recorder.
VU meter Volume meter indicates average level of sound.
Waveform monitor Oscilloscope with appropriate time-base for displaying the television waveform. Usually includes a face-plate graticule to indicate sync level, black level, peak white and percentage signal level.
Wavelength The length between adjacent peaks of a signal.
White balance The electronic process of defining a reference white lit by a light source of a specific colour temperature.
White noise Random noise containing an equal level of the audio frequency spectrum
Wide angle The horizontal field of view of a lens greater than approximately 40°.
Wide shot (WS) A description of shot size which includes objects greater than the size of the human figure.
Working-as-live Continuous recording with no opportunity for recording breaks or retakes.
Working behind the camera Operating the camera using remoted lens controls attached to pan bars and a non-monocular viewfinder.
Wow and flutter Variations in speed of a mechanical system, audible as frequency variations in an analogue recording.
Zebra exposure indicator A black and white striped pattern that appears in the viewfinder at points in the picture corresponding to a pre-set video level. Used as an aid to manual exposure.
Zero level voltage A standard reference audio signal of 0.775 V at 1000 Hz used for audio equipment line-up.
Zoom A variable focal length lens achieved by internally moving elements of the lens.
Zoom ratio The ratio of the longest focal length to the shortest focal length a specific zoom lens can achieve.
Zoom tracking A lens pre-focused on a distant subject will stay in a focus for the whole of its zoom movement towards (or away) from that subject providing the back focus (flange back) has been correctly aligned.