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| A-B roll edit | An edit in which two or more players are used to create special effects such as dissolve and wipe, and one recorder is used to record the results of the edit. Using an editing controller allows efficient control of the VTRs and very precise editing. |
| AFM recording | Abbreviation of Audio Frequency Modulation recording. The recording of frequency modulated audio signals together with frequency modulated video signals in video tracks |
| AGC | Automatic Gain Control. Sets proper video gain control for low light shooting situations. video sensitivity gain is increased when the iris F-stop reaches a pre-determined minimum value. |
| Assemble edit | An edit mode for adding new scenes to the end of the existing recorded scenes. Continuity of CTL signals at the edit points is maintained electrically. In this mode, inserting new scenes into the middle of the existing recorded scenes causes noise to appear on the picture at the end of the inserted scenes |
| AVI | aerial video imaging or imagery - refers to the general technique of acquiring aerial imagery in a video format. |
| B-Y signal | One of the color difference signals, the B signal minus the Y signal. |
| Chroma Detail | Compensates for poor resolution in the high chroma (colour) areas of the picture. |
| Chrominance signal | Signal which carries information about hue and color. Also called C signal. |
| Color frame | The color subcarrier phase whose one cycle consists of two frames (four fields). |
| Color framing | A method to maintain continuity of color subcarrier phase from one two-field frame to the next, for the purpose of avoiding noise on the picture at the edit points. |
| Component signal | A video signal consisting of a luminance signal (Y) and two chrominance signals (R-Y, B-Y). |
| Composite signal | A composite video signal containing video. burst and sync signals |
| Condensation | Water which has condensed on tape transport mechanisms. Videotape tends to adhere to and be damaged by condensation on the head drum |
| CTDM | Abbreviation of Compressed Time Division Multiplex. A processing method employed to record color difference signals. When composite video signals are recorded, the narrow bandwidth color difference signals (R-Y, B-Y) are compressed by time division, multiplexed, and recorded in a single track. CDTM video is characterized by its broad bandwidth and high picture quality. |
| CTL signal | Abbreviation of Control signal. in VTRs, regular pulses used to synchronize tape movement and the scanning position of the video heads. Recorded in a special track so that the video heads can scan the playback tape accurately. |
| Dark Detail | This circuit determines the optimum degree of contour enhancements to the dark areas of the picture, to deliver crisper, cleaner, more natural looking images under challenging lighting conditions. |
| Data Code | Allows the user to store date and time information on the videotape. Information is automatically encoded. Indicates the date (year, month and day) and time (hour, minute and second). |
| DGPS or Differential Global Positioning System | normal GPS data has an inherent error intentionally introduced in the satellite signals; this error is typically around _100m. However, the error can be corrected either during the survey (real time DGPS) or after the survey (post-survey corrected DGPS) to produce positions typically accurate to _5-10m. For survey data to be DGPS corrected, special handling of the data is required. |
| Digital Signal | Using digital circuitry to process the video image brings benefits in: 1) higher performance, 2) fine adjustment of a variety of video parameters, 3) flexible and higher quality image processing. Includes such parameters as (see) Chroma Detail, Dark Detail, Highlight Compression and Flare Correction Circuits. |
| Drop frame mode | In NTSC format, the actual number of frames per second is approximately 29.97, while that for the time code is specified as 30. Drop frame mode is a mode in which the time code is advanced in such a way that the difference in frame value between real time and the time codes is corrected. In this mode, two frames are skipped at the beginning of each minute, except for every tenth minute, so that the frame value for time codes matches that for real time. |
| EE mode | Abbreviation of Electric to Electric mode. Video and audio signals are supplied to the VTRs internal circuits, but not to the recording heads. |
| External synchronization | Synchronization of the signals and tape transport of a VTR with those of a reference VTR. |
| FIT Processing | Frame Interline Transfer. CCD type image sensors. |
| Flare Correction Circuit | Compensates for unsteady black caused by light or by a subject's movements |
| Genlock | Abbreviation of Generator Lock. The pulse generator built into video equipment is adjusted to synchronize it with an external reference signal. |
| GPS or Global Positioning System | the Global Positioning System is a satellite positioning system that typically provides positional accuracy of _100m with the use of an appropriate receiving system, some of which are hand-held. The GPS data can be corrected to produce accuracies as good as _5-10m (see DGPS) with minimal processing. With special survey-grade processing, accuracies of _1-2m are possible. |
| Highlight Compression | This circuit expands the dynamic range of the highlighted areas and prevents halation. Provides detailed images even against bright backlight or daylight. |
| Hyper HAD | Hole Accumulated Diode. CCD type image sensor. HAD type CCD offers high resolution (600 lines). |
| Insert edit | An edit mode for inserting new scenes into the middle of existing recorded scenes. The recorder uses the CTL signals already recorded on the recorder tape to control tape movement. Before editing, VBS signals must be recorded over the entire length of the recorder tape. |
| Intelligent Auto Iris | Automatic control of the camera's iris. Very practical when there is an extreme difference in the brightness of an object and the background. The iris automatically adjusts to compensate for this difference. |
| LANC | Local Application Control Bus System (Sony). Allows connection of a Handycam to another VCR or editor. |
| LTC | Abbreviation of Longitudinal Time Code. A time code recorded in a separate track at the edge of the tape. |
| Luminance | The signal which carries information about brightness. Also called the Y signal. |
| Lux | A measure of light usually in foot candles. |
| Metal tape | Magnetic tape coated with a fine metallic powder of needle-like spines mixed with a binder. Metal tape is noted for its high recording density. |
| Non-drop-frame mode | A mode of advancing the time code in such a way that the difference in frame values between real time and the time code is neglected. Using this mode produces a difference of approximately 86 seconds per day between real time and time code, which causes problems when editing programs in units of seconds using the number of frames as a reference. |
| Oxide tape | Magnetic tape coated with needle-like spines of ferrous oxide mixed with a binder. |
| Phase synchronization | When editing with two VTRs, adjustment of the movement and position of the recording and playback tapes, carried out while the tapes run from the pre-roll position to the edit in point, in order to increase editing precision. |
| Program AE | Programmed Auto Exposure. The shutter speed automatically adjusts to match lighting conditions. Some cameras offer several modes for differing situations. |
| Record Review | Playback of the last recorded scene. |
| Reference video signal | A video signal consisting of a sync signal or sync and burst signals, used as a reference. |
| RC Time Code | Re-writeable Consumer Time Code Generator. Indicates the absolute position of the tape with hour, minute, second and frame |
| R-Y signal | One of the color difference signals, the R signal minus the Y signal. |
| Search mode | A VTR mode used when searching for specific scenes by viewing the video picture or time codes while rewinding or playing the tape fast forward. |
| Servolock | The mechanisms which control the phase of the head drum and the speed of tape transport during recording or playback are called servo mechanisms. Servolock is synchronization of drum rotation and tape speed with a reference signal |
| Scene File | Customized digital parameter settings. Digital processing of the video signal (e.g. colour correction, background lighting, dark detail). See Digital Signal Processing. |
| Shutter | Electronic shutter works in conjunction with the iris setting (F-stop)and, in higher shutter speeds, eliminates the blurred image of fast-moving subjects. See Program AE. |
| S/N | Signal-to-Noise ratio. The higher the signal-to-noise ratio, the better is picture quality. |
| SMPTE | Society of Motion Picture and Television Engineers. |
| SteadyShot | Optical Image Stabilizer (Sony). Compensates for camera shake. |
| Superimpose | To superimpose two or more video images in layers. |
| S-VHS | Super VHS. Format which offers higher video performance than regular VHS. Horizontal resolution is improved (often over 400 Lines). |
| Sync signal | A reference signal consisting of vertical and horizontal sync signals used for synchronizing the scanning patterns of the video camera and the monitor. |
| TBC | Abbreviation of Time Base Corrector. Electronic circuits to electrically stabilize the playback signals by removing color variation and roll in the playback picture caused by irregularity in drum rotation and tape movement. Time base correction reduces deterioration of picture quality when transmitting or copying playback signals. |
| Time code | A digital code recorded on the videotape to supply information such as the hour, minute, second and frame of each frame. LTC and VITC are time code formats. |
| Tracking | Control of playback tape speed in such a way that video heads are able to scan the recorded signals correctly. |
| User bits | Sections of the digital time code signal left open so that the user can record any information which may be necessary, for example the actual clock time. |
| VITC | Abbreviation of Vertical Interval Time Code. A time code inserted during the vertical blanking interval between two fields. Unlike LTC codes, VITC codes are stored in the same tracks as the video information, so they can be read even while the tape is not moving. |
| V-blanking | The portion of the video signal that occurs between the end of one field and the beginning of the next. During this time, the electron beams in the cameras and monitors are turned off so that they can return from the bottom of the screen to the top without showing traces of movement on the screen. When the position of Vblanking is not adjusted correctly, a horizontal black bar appears on the screen. |
| VBS | Abbreviation of Video, Burst and Sync. A composite signal consisting of video signal, burst signal and sync signal. |
| Video gain | Amplification of video signals, expressed in decibels (dB). |
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