DVMG  Fact Sheet Number-6

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 How to Save on Video Editing
(Off-line On-line Video Editing)


Eric Kenning

The following is a method used by professional production houses to overcome the lengthy time needed to edit and carry out post production work such as composing music, titling etc.

Editing is the most important step in a film or video tape production. A production which has been well shot will be a total waste if poorly put together. A good editor combines artistry and technique so the finished production flows smoothly. It is not unusual for a 10 minute production to require several weeks of editing. There is no difference in the time, or creative skills needed to edit a film or video tape production, the difference is only in the technique used. Film is cut and joined, and video tape is edited electronically.

Desktop video editing misleading

Today, computer video editing has resulted in a lot of hype and misinformation. In reality there is no such thing as a system that can be run on your office desktop and used by anyone who can operate a computer. It seems to be a fantasy that we can get rid of all the professionals and use a computer to turn out a professional looking video ready to broadcast on television. While these systems can physically do the job, editing technique is still the key to a successful production.

Let's now look at a system that was first developed over 70 years ago by the film industry. In film editing, a work print is made from the original camera negative and is used for all the editing work. This is done to avoid any damage to the original negative. The work print is then edited by cutting and joining using tape. The editor is free to cut and re-cut, to take pieces out and put them back without effecting the negative. Later the original negative is cut to match the edited work print.

Video tape editors were quick to see the value of the film work print idea and developed a system called off-line/on-line editing. One benefit was the overcoming of the high cost of editing on broadcast video tape equipment. This is achieved by copying the original camera tapes onto VHS which become the equivalent of a film work print. Editing is carried out on the VHS tape off-line. When the VHS work tape has been edited, a final edit is carried out using the original camera tapes and is called on-line editing.

Let's consider each step in more detail.

A copy of the source material originating from a Betacam or digital camera, is made with a 'time code window' of eight numbers. The numbers are broken up into four groups representing hours, minutes, seconds and frames, and will look like this:

The time code can be displayed on the top or bottom of the screen and is generated by the camera and recorded on the camera tape at the time of shooting. The time code is later transferred to the VHS tape with the vision and sound and is called a 'burnt in time code'.

When the tape is edited it will be broken into a number of 'shots'. The start of each shot is called the 'in-point" and the end the 'out-point'. It is the time code of the 'in' and 'out' points that will be used to find the shots in the original tapes during on-line editing.

When the off-line tape is completed, a time code edit list is made in preparation for on-line editing. This list is called an 'EDL' (Edit Decision List) The EDL lists all shots with their time code in and out points. It will also list any effects, ie. split screen, rotating the image, zooming, squeezing, dissolves, fades, titles and graphics as well as the sound requirements.

The introduction of computer video editing now makes it possible to edit video on a system called non-liner editing. However, the same principle applies, editing high quality video demanded by television requires a high investment in software and equipment. It is not unusual for it to be in the hundreds of thousands of dollars. Because of the high cost the hourly rate will be in the $150 to $300 an hour range.

As you can see, editing and post production using a broadcast quality non-liner editing system would be costly and restrict the creative time needed. On average, a 15 to 20 minute video will require approximately 60 to 80 hours of editing. Off-line editing can be carried out on a multimedia computer using software costing under $500. Keep in mind, however, that video editing even at the lowest quality, requires massive disk storage and may tie your computer up for weeks. One way out is to transfer your edited sequences to a VHS tape as you edit them. The VHS can be used by other production people for script writing or for viewing by a client.. The quality of the images on the screen is not important as each shot will be replaced when the on-line edit is carried out.

When you're ready for on-line assembly, you transfer the time code information to a shot list called an edit decision list (EDL) While you can transfer the EDL information electronically, most producers will tell you it is best to use low track equipment namely, a pen and a piece of paper. Your EDL along with your original footage will go to a post production house. The on-line editor will create a frame-for-frame edit from your high quality camera original using the information from your EDL and put in all the special effect.

Notes from "Script to Screen Seminar". ( Eric Kenning.