Creating Simple Burn-ins on
Your Avid Outputs
by Bob Berman
When turning your show over to sound and music, it is usually necessary to add a continuous timecode and footage burn-in on your output tapes. Depending on what deck you’re using, you may
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What is described below is a process that will simply and cheaply create a frame-accurate footage burn-in. It requires no additional equipment and the only cost involves creating a master tape with appropriate burn-ins that will be digitized once and then cut into your outputs.
Create a Tape
A tape must be created through telecine that provides a continuous footage counter. To make sure that the numbers are accurate, the telecine may want to transfer some leader, or they may simply be able to roll the telecine with no film loaded and record the output. Either way, begin the counter at 0000+00 and 01:00:00:00 and run the transfer for a bit longer than your longest cut reel. If your reels are 20 minutes long, create a tape that runs at least several minutes longer.
The numbers should be white over a pure black background and should be placed wherever you want them to appear over your outputs. It is not essential that placement be exact since the numbers can be moved in the Avid. And though the size can also be changed, it is generally easier to read a reduced type rather than an enlarged one; therefore, have the font scaled to what is called "large" in telecine.
The start mark, at 0000+00 and 1:00:00:00, should occur on an "A" frame. If you normally make tapes with a specific amount of pre-roll before the start mark, then ask that the counter be started earlier, but be sure it begins on an even footage. To add two minutes of pre-roll to your tape, start the counter at 9820+00 and 00:58:00:00.
Once the tape is complete, digitize it as a single master clip, being certain that the frame count is accurate. Check that the frame counter advances exactly a single frame every time you advance the Avid a frame and be sure that you do not see superimposed frame counter numbers. Check the first and last few feet by going through them a frame at a time. If your burn-in includes a pull-down phase indicator (‘A’, ‘B’, ‘C’, ‘D’), you should never see the letters superimposed. You can also use the phase indicator to quickly check the whole reel. Hold down the 8-frame button and go through the whole clip, watching the phase indicator. If the pulldown sequence is consistent, it will look like a continuous freeze frame. If it changes, you have a pulldown problem at the point where the change occurs. Check your ‘A’ frame and digitize again or send the tape back to telecine and have it redone.
Settings
In your user settings, go to the Effects setting and change the default from "Real Time: Wipes" to "Real Time: Keys." This enables the real-time use of the Luma Key effect, which will allow you to add the burn-in to your outputs without rendering. Most recent Film Composers offer real-time luma keys, but if your system doesn’t, then you’ll have to render the entire reel, which will take up a large chunk of time and drive space.
Cutting the Counter In
First, duplicate your sequence. Because we will be adding elements to the cut picture, you will be better off leaving the original for cut lists, EDLs, etc.
In your duplicated sequence, create a new video track. Cut the footage counter into your sequence so that 0+00 falls on the picture start mark. In the Effect Palette, choose the "Key" option and drag the "Luma Key" icon onto the footage counter clip. The footage counter should now appear over your cut picture (be certain that you are monitoring the upper most video track). You should be able to play the sequence and, without rendering the luma key, see the running counter displayed over your picture. To make sure that the counter is accurate, display Master Footage above the record monitor. Compare the counter you’ve created to the master footage. It should match exactly throughout the reel. Go to the end of the sequence and park on the LFOA or the tail pop and do a final check there.
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the ‘property of…’ titles above it. |
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Note that any effects that are present in your cut sequence that run on the video tracks below the counter/luma key will need to be rendered. This is because most Avids cannot run two real time effects concurrently (there is at least one exception, which I will explain below).
Making Adjustments
You can adjust the footage counter by going into Effects Mode and highlighting (clicking on) the luma
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No Place for the Footage Counter?
The counter will be most readable if you can place it over a black background. If your dailies are letter-boxed, it’s best to position the counter over a portion of the existing black frame. If you must place it over the scene itself, you can improve readability by creating a black surround for the numbers.
To do this, perform all of the above steps. Then, in the Effects Editor, slide the Gain control all the way to the left so that it reads zero (the default). Then slide the "Lum" (Luminance) control to approximately 100 (experiment with this setting for optimal readability). The screen should now be entirely black but for the numbers in the footage counter. Then use the "Crop" sliders to reduce the size of the black area surrounding the numbers until all that remains is a black box containing the counter. You can then move this counter-in-a-box to any position you like, as described above.
‘Property of…’ Title
As mentioned earlier, there is one instance in which two real-time effects can play concurrently. The Avid allows real-time titles to play above some other real-time effects, including a real-time luma key (the reverse is not true: the title must be above the luma key). This allows you to create a "Property of..." title, or a title indicating the version number or reel number, and cut it into a new video track. (Since the Avid limits a title source clip to a length of two minutes, you’ll have to cut the title into the sequence as a series of two-minute clips.) This will allow you to create tapes that will satisfy most studios’ copyright requirements.
What About Timecode?
So far I’ve described a method for adding a footage burn-in. But most sound and music editors will want to see a continuous timecode display, as well. Timecode burn-ins can be created in two ways.
The easiest and simplest method is to ask your telecine to include a continuous timecode counter on the footage counter tape they make for you. Then when you digitize this tape and create your luma key overlay, you’ll be applying timecode and footage counters simultaneously. The drawback is that in a 24 fps project the timecode numbers will be altered in the digitizing process, as the Avid turns your 30 fps counter tape into 24 fps media. The result is that in your output, every fifth timecode frame number will be skipped and every fourth number will be duplicated to make up for it (or, if your digitize settings are set for ‘Combine Fields’, one frame in five will appear as a superimposition of the two adjacent frame numbers). Check with your sound and music editors – many will not have a problem with this.
Alternately, you can have a timecode burn-in added during tape duplication. This should still be cheaper than adding a footage burn since the dubbing facility doesn’t have to lock the transfer to a telecine (without the telecine, footage accuracy is only ±1 frame).
In addition, some decks can add their own timecode burn-in, slaved to address track code (look for a jack labeled ‘Super’). Some models will allow you to add this window to a tape while it is being recorded, but others only enable the burn-in on the deck’s output. If that’s true, you can still use it to add a timecode counter to a VHS deck connected to your primary deck’s output. Use the display menu to supress the display of other deck functions and to move the timecode window around the screen.
You can also put audio timecode on a VHS tape during dubbing, by connecting your primary deck’s timecode-out jack to Channel 2 of the VHS deck. But be careful. Most consumer VHS decks don’t allow you to input separately to the HiFi and linear channels and they will sometimes mono the linear tracks even when the HiFi tracks are separated. You’ll need to experiment with your VHS machine to see what it does and work with your sound and music editors to see whether you can make something that will work for them.
Next Step
Until Avid chooses to update the Media Reader, those of us who begin using Film Composer v. 10 will have to find other ways to make footage and timecode burn-ins. The method I’ve described requires some extra rendering of effects and complicates your sequences. But it’s perfectly accurate, easy to check, simple to use and fairly flexible. I have used this technique for several years without problems and carry my original burn-in tape with me from show to show. In fact, I have the media backed up to a JAZ disk so that I can bring it to another Avid and avoid the digitizing time. Try it – it will save you and your production time and money.
Bob Berman is an assistant editor. His recent credits include 'The Way of the Gun',
Three to Tango' and 'Selena'. He can be reached via email
Reprinted from
The Motion Picture Editors Guild Magazine
Vol. 21, No. 5 - September/October 2000
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