Editing for television

Editing a television program is much more than putting the shots together

Why Edit?

One's first thought is that, if you wanted to assemble a series of shots back to back, you'd use the assemble edit mode, and when you wanted to insert a shot somewhere to replace existing video, you'd use the insert mode. This is not exactly true.

When in the assemble mode, you dub onto the record tape so you always add new, fresh control track. The recording VTR is supposed to make perfectly continuous control track in this mode. Unfortunately, even the best machines sometimes fail in this regard.

As a result, some assemble edits experience sync roll or momentary tearing.

When editing in insert mode, on the other hand, you do not transfer fresh control track to the record videotape. Instead, you use it as a guide and position reference for laying down the inserted video on the tape. Therefore, to do insert edits, you must first lay down a control track by recording black on the record tape, before using it for editing. This takes time, but you gain roll-free edits.

Time Code

Time code is a way of representing time and position information about a tape in either an audio or visual form. To identify and mark where all segments occur, various address code systems have been developed. The two most common are the control track or pulse-count system, and SMPTE time code.

Control Track Counter

The control track counter takes advantage of the control track pulses on the tape. These are counted, one by one, as elapsed time - one pulse per frame. The advantage of this system is that no special code needs to be recorded onto any videotape - either during the original shoot, or on the master edited reel. The disadvantage of control track counting systems is that they are not always frame accurate. You may lose one or two frames over the course of stopping, starting, and shuttling the machine.

SMPTE Time Code

SMPTE time code, on the other hand, is an electronic signal that provides an address for each frame of video. This address is recorded on the time code track of the videotape.

If you look at the audio time code signal as an audio wave, it appears as a sort of square wave at a frequency of somewhere between 2400 Hz and 4800 Hz. This signal, upon closer inspection, is actually at least 80 transitions (cycles) about every 1/30 second. The code itself is made up of 80 binary digits (bits) of information:

Time Code Bits
Bit	What It Does
0-3:	Frames units
4-7:	[Assignable bits]
8-9:	Frames tens
10:	Drop Frame bit
11:	[Unassigned bit]
12-15:	[Assignable bits]
16-19:	Seconds units
20-23:	[Assignable bits]
24-26:	Seconds tens
27:	[Unassigned bit]
28-31:	[Assignable bits]
32-35:	Minutes units
36-39:	[Assignable bits]
40-42:	Minutes tens
43:	[Unassigned bit]
44-47:	[Assignable bits]
48-51:	Hours units
52-55:	[Assignable bits]
56-57:	Hours tens
58-59:	[Unassigned bits]
60-63:	[Assignable bits]
64-79:	Synchronizing word

What Is Drop Frame Time Code?

Regular time code counts 30 frames per second. Colour television has, in fact, 29.97 frames per second.

In drop frame time code, frames 00 and 01 are dropped from the counter every minute, except multiples of 10 minutes (10, 20, 30, 40, 50, 00). 

Therefore, 108 frame numbers are dropped every hour (3.6 seconds), or one frame about every 33.3 seconds. Notice that it's digits from the numbering system that are dropped, not actual frames of video. You still have all of your video information with drop frame time code.

Rule of Thumb When Spinning Shows

"Spinning a show" is the act of quickly fast-forwarding the program, to get the final running time, instead of watching the tape in real time.

To calculate the real duration of a show that has been spun using non-drop-frame control track pulse counters, multiply the result on the non-drop frame counter by .999. If you've spun a show using a non-drop frame control track pulse counter by accident, subtract 3.6 seconds per hour, or 1 second for every 16.67 minutes.

Single-Source Editing

The two machines are operated via an editing control unit that allows: selection of precise edit points; control of VTR rolls; control of play and record modes (assemble, insert) and editing of audio and video tracks separately or together. Most units also allow you to: see and hear the tape at other than normal speeds; run a trial edit so you can rehearse it before actually performing it; trim the editing point frame by frame; perform split edits (edit video and audio separately without their affecting each other); and review the edit once it's been performed.

Non-Linear Editing

 cutting and re-cutting, inserting new material, and experimentation.

hard disk drives, providing random access from that digital storage. The editing process takes place on a computer, running appropriate software to perform various functions. The video and audio information is stored on large computer hard drives, where it can be viewed, modified, and eventually played back in real time from the system.

Editing Software

Throughout the film and television industry, editors use high-end pieces of editing software. These take digital files and allow for cuts, titles, transitions, and even effects. Some of the most popular software right now are:
Final Cut Pro
Avid Media Composer
Adobe After Effects
Potential editors should, during their college careers, become as familiar with these as possible. Using some less expensive or free software may be a good way to start developing your skills.