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Introduction
For those of you who are not very familiar with Adobe Premiere or the Film Matchback problem, there are several points that you should understand before tackling the subject:
• Keycode numbers taken from the bar-code reference in the edge of all film negative done today are an exact reference to the edge numbers that are imbedded on the film stock 16-frames per 35mm foot and 20-frames per 16mm foot. At the moment of the film transfer to video they are burned-in over the video image, usually in the bottom-right side of the frame, to be used as a guide for cutting the original film negative after the film has been edited on a non-linear editing system. Keycode does not generate an audible signal for reproduction on other machines like it does for SMPTE Timecode, so the only reference to the original Keycode is the burned-in information found on the videotape generated by the transfer method.
• SMPTE Timecode is also generated at the moment of the film transfer to tape and is usually recorded on the bottom-left side of the frame. Since this is an audible tone recorded on a special track on the tape, it is used as a method to reference back to the Keyframes that it is in parallel and is the method used by different manufacturers of Keycode-generating equipment like Evertz Microsystems to generate a floppy-disk with all of the pertinent information for almost-perfect synchronization of Timecode/Keycode while using a system like the Avid Film Composer to do film matchback.
• Unfortunately Adobe Premiere does not include in its software the function of reading an Evertz-generated floppy disk, so we have to resort to other less sophisticated methods for doing a film matchback, which is the reason for this article. The following information which has been compiled after doing several professional jobs and experimenting long hours with the program to arrive at the suggestions which we are posting here, should in no way be taken as a final ideal procedure due to the many intricacies and pitfalls that are generated by the restrictions that are imposed by the «not-so-perfect» NTSC video standard.
• Since normal NTSC video runs at 30 frames per second (with two video fields per frame), the 24 frames generated by a film project have to be “expanded” to 30 frames to conform to the standard. In a normal telecine projector this is done easily by replacing the 4-sided shutter in the projection plate with a 5-sided one, which permits 5 frames to be created for every 4 projected. This obviously creates the necessary additional 6 frames-per-second necessary for the 30-frame NTSC standard. No problem here. But the real “standard” for transfering film to videotape is usually the Rank Cintel telecine which uses a system called the 3:2 Pulldown which creates two fields from one frame, then three fields from the next, then two again, and so on, creating the necessary 30fps/60fields second that we see on videotape. Fortunately, upon transfering your material with the appropriate video card into Premiere, the two video fields are eliminated and we’re back again to the normal 30-frame NTSC video standard. But in this conversion we’re losing 50% of the fields created by the Rank Cintel transfer. Visually this doesn’t affect us very much, but in terms of the film matchback, it does. When the 3:2 Pulldown scheme is used, the Keycode numbers created follow a regular 2-3 pattern and each number has an appropriate A,B,C or D letter following the individual frame (when it falls on a “real” frame) and B and C underlined letters for those that are duplicate or virtual frames. Of course, there are a lot of virtual frames with A,B,C and D markings, but most of them are lost in the digitizing process and in Premiere. In the 24-frame Premiere Project Preset the program simply eliminates every 5th frame of video in the normal 30 fps. transfer material. This is done indiscriminately beginning with the third frame from the start of each individual clip that is in the project or when you select the 24-frame option in the Clip Window Options. Of course, by following this simple process, Premiere is automatically eliminating 36 fields from the 60-fields of transfer, thereby destroying all the purpose of the 3:2 pulldown scheme markings, making it difficult to sort out the real frames from the duplicates. We’ll discuss how to fix this further on. Now let’s start from the beginning:
The Transfer Process
First of all, get a good transfer from your post house and make sure that they give you very good (meaning, large and readable) burned-in Time Code and Keycode numbers, well within the safety-viewing limits. Your eyes will thank you for this.
Transfer Format
Record your transferred footage on a format that you can easily use at home or in the office, like VHS. The added quality of Betacam SP or whatever will only cause you problems and a lot of extra dollars if you don’t normally use that sort of equipment and have to rent out.
Digitizing Your Material
When digitizing your material use a good I/O video card that gives you exact information about dropped frames. I use the Matrox Rainbow Runner which is about as inexpensive as you can get, but which gives you dropped frames read-outs and has excellent quality even in the lowest resolutions. Getting your material into your computer without dropped frames is an absolute must for your negative matchback. If possible (and if you can identify them), jot down your camera roll numbers at the moment of giving your clips a title. For example: Roll 006-Girl on Swing.avi.
Recording Timecode on Your Material
Once you have all of your material in the computer perfectly labeled and ready to go, open your Premiere 4.2 program and use any of the 30fps Project Presets to start your first ppj. Import all of your clips into the project bin and start with what is initially a very boring, but useful task: double-click on each of your scenes and open the Clip Window and select the Clip pull-down menu where you will find Timecode near the middle of the list. Click on it and write the exact timecode numbers of the first frame of each clip: 30fps, Non-drop Frame, File Beginning and the number of the reel that the clip belongs to. Even though this information is not absolutely indispensable for the success of your film matchback it does provide you with (a) an EDL readout, (b) gives you a «second reading» for comparing the length of your shots and (c) gives you an easy method to check if you have any dropped frames (if you go to the tail of the clip and the numbers on screen aren’t absolutely identical to the Premiere read-out, you’re missing frames somewhere). The information that you record at this moment will become an integral part of that clip wherever you take it within Premiere, so you only fill it in once and that’s all.
The Final Edit
After you have done all of this, you can start a New Project with the 24fps Project Presets this time. From here on you can do all of your editing without worrying about anything else until you have what you consider your absolute final cut and you’re ready to tackle the Keycode problem and your negative matcher. Up to this point this can be a process of days, weeks or months, depending on your project. You must be totally certain that what you’ve edited is what you want to see exactly on the movie screen and that you’ve taken care not to duplicate shots or intercut scenes without keeping in mind the frames which will be lost in the splicing process of film matching and preparation for final printing. As is usual in film work, make a 1-frame beep signal in the sound track (use the 1khz_snd.aif sound tone from the Goodies section in Premiere) exactly 48-frames (2 seconds) before the first frame of picture and follow the same procedure in the tail end of your project so that you can have two perfect sync marks for checking your sound track to your picture.
Render and Re-Name Clips
What follows is the most crucial part of your work and the one that is most «human error»-prone, so please take it with a lot of patience and it won’t seem like such a bad thing in the long run. First of all, make sure that you’ve made several backups of your .ppj project (remember Murphy’s laws) and if you’re an orderly person take a few minutes (or hours, maybe) and go through your project, clip by clip, in chronological order, and render each one of the pieces into a new .avi, numbering each shot 001.avi, 002.avi, and so on. When you finish this job, open up a New File in Premiere and Import all of your newly renamed clips. Since they’re in chronological order, you can select them all and dump them into the new Construction window of your project, which can be named Matchback or whatever to set it apart from your other projects. This may seem like a waste of time, but in the end it will be very helpful in immediately finding a clip or clips that you need to review at a later stage and it gives you an orderly sequence to your edit.
Logging Keycode
Now that you’ve gotten everything in order, you can start logging each clip one by one. Open your first clip in the Clip window (or in the monitor if you have one) and jot down the following information: The exact number of the first Keycode frame (keep in mind that the first numbers are the film stock reference, so only use the next four numbers, followed by a plus sign, another number and a letter, such as: 5677+12B or 5677+12B. If the letter has a line below it like in the second example, it means that you’ve hit a «shadow» or «virtual» frame created by the 3:2 Pulldown scheme of the transfer machine. At this point (the beginning of a new scene), you have to clearly identify if this frame is «real» or «imaginary» because you stand a 50-50 chance of throwing your audio sync off one frame and if this compiles over a lot of scenes, you can just imagine what will happen. If the frame you have selected has fallen on a clear A, B, C or D frame, jot down the number and continue to the next step. If, on the other hand, it falls on a B or a C underlined frame, there’s a good possibility that the number is not the correct one. Here is an example of an uncorrect reading of the first three frames of a scene: First frame: 13B, Second frame: 14C, Third Frame: 00A. In 35mm, each foot of film is comprised of 16 full 35mm frames (the 16th frame is the 00 found above), which is also handily the full turn of a 35mm synchronizer wheel. Our example above should really read: 14, 15, 00 instead of 13,14,00, so jot down 14 as the frame number and NOT the 13 that you see on the screen. Here’s another uncorrect example: 09B, 10C, 12A (should read: 10, 11, 12 - so 10 is the number and not 9). A correct reading is: 10C, 11D or 11C, 12D. The rule of thumb is to dig out the underlined letters and go frame-by-frame until you find a clear lettter A, B, C or D, then backtrack, counting backwards until you hit the first frame of picture and you jot down the new number. Sometimes it’s the right number, sometimes not. Once you’ve written this down, proceed to the end of the clip and jot down the exact Keycode number that you find there (don’t worry about the end letter being underlined or not - I’ll explain later). The information gathered here should be consigned in the appropriate boxes in the excel spreadsheet. 16mm will also follow the same pattern, only that instead of moving in 16-frame increments, it moves in 20-frame ones.
Frame Number
 At the same time that you open the Clip window to jot down the Keycode numbers, you should locate your cursor over the blue line at the top of the window and press the right-side of the mouse, which opens the Clip Window Options menu. In the smaller window named Count, select Frame Number and press OK. The LED readout at the bottom of the opened Clip Window will now read in frames only. Jot down the bottom number, which is the exact number of frames in your clip. This information is of utmost importance because this is going to be your guide in the whole matchback process. You will notice that the frame number above the one we have mentioned will be lacking 1 frame at the end of the clip. That is because this counter starts rolling from 0, so don’t worry about the discrepancy. The results should be inserted in the Premiere 24fps boxes in the Excel speadsheet.
Timecode EDL Readout
Make a print-out of the EDL readings generated by the ppj file. Go to Export in the File menu and choose the CMX 3600 EDL which will open a small window with the following default settings: Title: _____ Start Time Code: 01:00:00:00, Frame Rate: 24 fps, Audio Processing: Audio Follows Video, Level Notes: Keys Only. Since we don’t need to change anything, click on OK and open the Save As EDL window where you will give it the appropriate name for identification purposes. As soon as you do this, the EDL will open on screen. Print it Out so that you can insert the information in the Excel spreadsheet. You will find four columns on the left and four rows of Time Code numbers on the right. If you’ve done your homework correctly, you will find that the first column on the left contains the numbers of your scenes in perfect chronological order, starting from 001 to whatever. The next column will have the information regarding reel numbers that you were supposed to fill in when you jotted down the Timecode number of each one of your clips. Your negative matcher will love you for the rest of your life if you were smart enough and jotted down the exact camera roll for each take (a difficult task if you didn’t number the rolls when you digitized your material at the beginning of this saga). The 4 Time Code columns on the right are tightly printed one after the other, so you should draw a line between them to separate them and make your life easier. The first column is the Time Code In number of each clip, the second column is the Time Code Out number of each clip (you will find that the last number is +1 more frame than what you read on the monitor screen - not to worry, it’s probably the same problem that happens when you mark Frame Number in the Clip Window and it gives you a -1 reading - the final arithmetic is okay, believe me). The third column is the accumulated Time Code total (individual clip In point) and the fouth is the accumulated Time Code (individual clip Out point). Jot down in the Excel spreadsheet the exact Time Code In and Out numbers in the appropriate boxes. The spreadsheet will automatically figure out the frame numbers of each clip at 30fps, make the conversion to eliminate the 5th “virtual frame” and will compare it with the Frame Number information that you have stored for each clip.
Xtra Frames
If you have followed all the instructions down to the letter and you have patiently and carefully jotted down the correct information in the appropriate boxes of the spreadsheet, you should be confronted with a row 40 to 60/70% filled with 0’s in the boxes under the heading of Xtra Frames. In the other boxes you will probably find a lot of -1 or +1 numbers. Don’t worry, this is perfectly normal in this unnormal world of film matchback. It just means that these are scenes where the 4:5 algorithm didn’t work out and it left an extra frame hanging on or out of the piece. This can be fixed easily by retracing your steps to the faulty clips where you will double-check your Keycode numbers at the Start and End of each edited shot. If there’s a mistake, it will show up right away and you should correct it in the spreadsheet. But if everything is correct and you still have a + or - frame, then just simply add or subtract a frame from the End of the shot. This happens even in the best of families (like Avid, for example). It’s just one of the pitfalls of non-linear editing, 3-2 pulldown, 29.97 video, drop and non-drop, etc., etc., etc. If the mistake is much larger, let’s say + or -10, or 14, or whatever, re-check every number of your Keycode and Time Code of that particular clip and you’ll quickly find the culprit. Also, remember that if you weren’t careful during video capture, you might just have included material with dropped frames and that’s what is causing the missing or extra frames. There’s a lot of «human error» in this portion of the work created by what is basically a long, dull, repetitive process that perfectly lends itself to sloppiness if you’re not careful. Fortunately the Excel spreadsheet will quickly bring you back to your senses. Keep in mind that if you do this part of the job to perfection, your negative matcher will not have additional problems and insecurities that will hinder his job.
Totalized Conversion in Frames
As a final and conclusive part of the matchback process, the Excel spreadsheet will automatically figure out the individual total in frames (Total Sum) as you go so that the negative matcher can put together the material with a frame-readout synchronizer that will give him the perfect frame-by-frame total at each splice to instantly double-check his work, clip by clip. The conversion to film feet and frames has to be worked out by hand since there are no formulas in Excel to work out uneven numbers.
Sound Sync
Here is a problem that is probably harder to figure out than the matchback process because there isn’t a crystal-clear solution to it. Some people strike a one-lite silent workprint from the final edited negative and transfer the mixed sound to a perforated mag track so that they can test the sync on a flatbed. This is about the best method to use because you can check your edited material as it will be seen in the final print, but it is costly. The other ways are to use a Nagra or a DAT to record the final mix from your Premiere timeline, transfer the sound to optical and cross your fingers that everything will work out in the end. Before stricking a final print, you can check your sync on a two-gang synchronizer with the original negative and the optical track. The sync marks (beeps) that you made at the Head and the Tails will inform you immediately if you’re out of sync. The same thing can be done with a perforated mag track and the original negative, by-passing the workprint. The main problem here is that it’s very difficult to verify at what actual speed the sound is rolling (30 fps? 29.97 fps?) and if it’s not rolling at the exact 24-frame speed of the film, how in the devil to fix it without a lot of expensive experimentation. Also, many people would rather do their final sound on ProTools or in a special sound sweetner, so maybe making the one-lite workprint is not such a bad idea... I’m wide open for suggestions.
Julio Luzardo is a film producer-director working in his native country of Colombia where he also teaches film and television directing, writing and cinematography. He can be reached at jluzardo@usa.net.
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