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T€aH n€ujr Videotape Editing and Program Assembly no. 8 in a series of 10 by rodger j. ross When the Ampex video recording system the start a portion of the original recording The next step was the development of was announced in 1956, almost at once containing the first scene is dubbed onto programmed editing with frame accuracy. users began insisting on the need for the master tape. The next scene is then This was accomplished automatically by editing facilities. At the time, the best located in the original recordings and means of tone bursts recorded in the cue suggestion Ampex engineers could offer cued up on the playback machine. (In the track of the videotape. This development was to cut the videotapes with a razor early days of electronic editing the practice offered the very great advantage that an blade and join the two ends together with was adopted of putting cue marks on the edit could be previewed (simulated) — a piece of sticky tape. But it was not long tapes with a felt pen to indicate the splice and if necessary adjusted — before actually before much more sophisticated splicing point between scenes.) The two machines making the edit on the master program and editing methods were devised. are then started, both in the playback tape. A Canadian, Norman Bounsall, who mode, and at the point indicated by the With this method of program assembly went from the National Film Board in cue marks, the machine carrying the tone bursts are recorded in the cue track Montreal to work at the Ampex Corp. in master tape is switched by the operator to at the points where edits are to take place, the United States, was responsible for a the record mode. Sophisticated solid state determined as before by playing back the major advance — electronic editing — electronic circuitry takes over to make the tapes several times to find just the right described in the February 1962 issue of splice at the next following frame synchro­ points in the action. Then, instead of SMPTE Journal. nizing pulse. putting cue marks on the tapes, tone Electronic editing enables portions of bursts are recorded by pressing a button. recorded programs (scenes) to be dubbed Programmed Editing with In the preview mode, the tone bursts (electronically transferred) to a program Frame Accuracy automatically switch the machine outputs master tape leaving the original recordings Electronic editing opened up a whole to the television picture monitor only, to intact No cutting or splicing is involved in new world of program production pos­ show where the edit takes place. If the electronic editing. The video and audio sibilities on videotape. But even with this result is not acceptable, the tone bursts in tracks on the tape being used for assembl­ important development the editing pro­ the cue track can be advanced or retarded ing a program (the master tape) can be cess was still a painstaking and time- by any desired number of video frames to erased automatically in exactly the proper consuming operation, in no way compar­ obtain just the right effect Then the edit locations in an already transferred scene, able with film editing methods. A basic can be made on the master tape by so that new video and audio tracks (for difficulty with videotape is that the recorded switching the machine from "preview" to the next scene) can be laid down on the pictures can be made visible on a television "edif mode. tape, giving the effect of a straight cut picture monitor only with the playback between the two scenes. machine running at precisely the right SMPTE Time and Control Code To make a splice between two scenes, speed (locked to television synchronizing This development greatly eased the two recorders are needed, one in the pulses). task of the operator in making edits and playback and the other in the record While electronic editing considerably seemed at the time to be the last word in mode. The original recording, which may enhanced program production on video­ sophisticated videotape editing. But there be'from a live television camera or from tape, production people and videotape was still the problem of locating a particu­ film transferred in telecine, is placed on operators soon began to realize its limita­ lar scene in the original recordings, a task the playback machine, while a blank tions. Its greatest weakness was the de­ that took up an inordinate amount of time videotape is placed on the record machine pendence on the operator's reaction time during videotape editing sessions. Until to become the master program tape. At and manual dexterity. Finding just the the introduction of random access editing right places in the action to make a in the late 1960's, production people Long time Supervisor of Technical Film "splice" between two scenes required could only give the machine operatqrthe Operations at th^ programming centre of mnning the machines back and forth over approximate location of a wanted scene CBC, Mr Ross is the author of two books, the same parts of the scenes several in a recording, usually by elapsed video­ Television Film Engineering and Color times. Then, in making the edit it was tape running time. Only after a scene had Film for Color Television, has won the only by good luck that the splice between been located and verified could the editing Agfa-Gevaert Gold Medal awarded by the two scenes occurred in just the right points be selected. the Society of Motion Picture and Tele­ vision Engineers, and is presently part of the action, dependent on the Several companies, including Advertel Chairman of the SMPTE Board of Edi­ operator depressing the record button at in Toronto and Central Dynamics in Mont­ tors. exactly the right instant real, developed systems of time coding 30/Fcbruary 1980 videotape to identify recorded scenes, This eariy development has survived at readout (recognizable numbers) super­ and to enable the playback machine to the CMX 600 editing systems. Other imposed in the pictures. These 3/4-in. automatically locate the start of any scene models, including CMX 300 and 50, are video cassettes are then taken away by in a recording by the corresponding time also available, as well as similar systems the production group to prepare the code. The "address" in the SMPTE time from a number of other manufacturers. edited programs. and control code, eventually adopted As the video cassettes are being reviewed and made official in American National On-Line and Off-Line in less costly helical scan machines, an Standard 098.12-1975, consists of binary Editing Methods edited program structure begins to take code groups recorded in the cue track, During the past two or three years the shape, and the edit list is prepared by identifying each frame by a unique num­ microprocessor has become the key build­ noting down on a sheet of paper selected ber. The code numbers can be displayed ing block in videotape editing systems, scene descriptions, reel numbers and the on an electronic counter, and used to and the application of the computer to time code numbers at the beginning and identify scenes as the time recordings are videotape editing has vastiy enhanced end of each selected scene. Sometimes a being made, and also to provide instruc­ the flexibility of videotape post-production. video "workprint" is made by assembling tions for the machine operator during Two methods of editing are commonly scenes on another 3/4-in. video cassette videotape editing. These numbers can used today. The on-line method consists in accordance with the edit list for final also be used to "instrucf the videotape of editing the original videotape recordings viewing and approval before work starts machine to locate a scene in the recordings to obtain the master program tape. In on the assembly of the 2-in. quadruplex and cue up the first frame of the scene on professional program production all of master program tape. a picture monitor, by simply punching this work is usually carried out on 2-in. With some computer-assisted editing the corresponding numbered buttons on quadruplex videotape recording machines. a keyboard. systems, the editing decisions are punched Off-line editing techniques have been as code blocks into a paper tape; with developed to enable time-consuming edit­ other types of equipment the editing Electronic Post-Production ing decisions to be made on another decisions are recorded on a floppy disc, a Systems lower cost videotape medium — usually magnetically coated flexible disc about In spite of these really astonishing 3/4-in. video cassettes. the size of a 45 rpm. audio record, with a developments, videotape editing was still On-line editing is the most convenient capacity to store up to 3000 edits on each being hampered by the inflexibility and methodin many of the simpler, less time- side. Upon completion of the cassette high costs of available systems, and es­ consuming decision-making situations. editing, aiito-assembly of the 2-in. program pecially the amount of time needed to Programs are buih up scene-by-scene, by master tape can begin, controlled by the make editing decisions, while simultan­ dubbing (transferring) portions of the coded information in the punched paper eously tying up scarce and very costly original recordings on one machine to the tape or floppy disc. professional broadcasting facilities. Among master program tape on the other machine, Writing in the August 1977 issue of the many proposals made to overcome utilizing, as a rule, programmed editing SMPTE Joumal, Arthur Schneider, an ex­ these obstacles was a system developed facilities as already described.

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