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TUTORIAL: Place 2-pops on the Leading Edge of the Frame


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I've gotten several requests to outline my procedure for popping scoring cues (for delivery to music editors) where the pops align exactly with the leading edge of the frame being popped. The following is a very simple procedure, and once you've done it once or twice it will become second nature. A 2-pop at the head is most common. Occasionally tail pops are added as well.



Logic provides for the standard division of a frame into 80 bits (or "subframes"). This added accuracy (not offered in every DAW) has a downside:  just because you're viewing a particular frame of picture doesn't mean that you're seeing that frame from the very first instant of it. Every frame has "width", meaning "duration". At 24 fps each frame displays for 41 milliseconds. On paper that might not seem like a lot of time, but when music or dialog is off by even one frame it can feel wrong against picture.)



1. To pop your cues you'll need an audio files of a pop. I have stereo and mono versions that I made myself. The waveform starts at a zero crossing and is very brief in duration. It's just a little sine wave burst at 1K.


I load my pops into the audio window at some point during production, and drag them as needed into the arrangement onto a separate track when the time comes to print. Let's assume it's time to print now and you've loaded your pops (head and tail) onto a track already, arbitrarily placed ---- 1 near the head of your cue and 1 near the tail of your cue.


2. Have a key command available to invoke "Pickup Clock (Move Event to Playhead Postition)"




HEAD POP: The head pop (or "2 pop") is placed approximately (if not exactly) 2 seconds before the start of music ("first music"). This rule isn't cast in stone, though I generally follow it. Sometimes I find it more convenient to place my head pop on an even second (frames = 00). Sometimes there isn't even 2 seconds available prior to first music. But generally, 2 seconds before "first music" is the place to align your head pop.


TAIL POP: Not nearly as important as a head pop, and in most cases can be omitted. That said, placement of the tail pop can be much more arbitrary. If a cue doesn't have a hard ending (fades out) or it has a long reverb tail, you might want to give that tail abundant clearance before introducing the pop.




A. Determine the exact frame of picture you want to pop. Let's start with the head pop first.


Scroll Logic's SMPTE counter (or the SPL) until you arrive at that frame. Write this number down. No, really, write it down. You'll thank me in the morning. ;)


B. At this point there's no way to tell if you are viewing the frame from its very first instant, somewhere in the middle, or even at the end. If you happen to wind up at the very end of the frame your pop will be, for all intents and purposes, a full frame off! As explained above, each frame is divided into 80 "bits" and the key to finding and popping the leading edge of the frame is to find the bits value that coincides with the precise moment when that frame first comes into view.


So let's find the leading edge...


C. Click/hold on the bits value in Logic's transport and slowly drag the mouse DOWN until the previous frame jjjjjjust comes into view. Continue to hold the mouse down and scroll slooooowly UP on the bits value until your desired frame comes into view. You are now at the leading edge of the frame!


You might want to rock the bits value up and down once or twice to ensure that you're at exactly the right place.


At this point the playhead is precisely located where the pop should be placed. Whatever you do, don't hit play or you'll have to do this procedure all over again. As a safety you might want to write down the timecode number you see in Logic's SMPTE counter. This way, if you mess up you can just re-type this number into the counter and not have to do the procedure all over again.


E. Locate and click on the (arbitrarily placed) head pop on your pop track. Hit the key command for "Pickup Clock". Bink! Your pop is now perfectly placed with the leading edge of the frame!


BTW, it helps to say the "Bink!" sound out loud every time you use this key command. :D


F. For tail pops (again, rarely required), just follow the same procedure to find the leading edge of the frame for your tail pop placement. Write this number down to provide to the music editor.


G. Print (bounce, whatever) your track with the pops.


That's it!

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Pop Audio Files


Below, a view of a stereo pop.



A closeup of how closely truncated the pop is, with start and anchor points at the very very beginning of the waveform. (What looks like a slight flat-line at the top of the waveform is an inaccuracy within the reduced-size image I've posted). There is actually no blank space at the top of the waveform, though it does start from a level of zero.



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Thanks Jay!


A 2 pop should always be EXACTLY 2 seconds before the cue begins. That is why it is called a 2 Pop.


Indeed. 99% of the time I do in fact place the pop exactly 2 seconds before first music. There have been some exceptions tho, including a few cases there weren't 2 seconds of footage available before first music. But yes, I agree, the pop should be placed exactly 2 seconds before first music whenever possible.


2. You didn't upload your pop sound


That's right. Go make your own pops!!!


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Go make your own pops!!!




Nice tutorial ski. I have to admit I cheat on this one. I bring my reference DV file into FCP and paste a stock countdown clip with 2-pop on its head and tail, export that out as a new DV, bring it into Logic and import the audio to a track.


Works a charm, but only if you have FCP! I'll keep your method tucked away for those times I don't have an easy out!



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So long as the cue remains file based do we really need to use 2-pops anymore? Obviously if the cue is going to tape a 2-pop (or 2 beep as everyone I work with calls 'em) is necessary, but if the cue isn't leaving the digital domain just include the timecode number as part of the file. That said, excellent tutorial.
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So long as the cue remains file based do we really need to use 2-pops anymore? Obviously if the cue is going to tape a 2-pop (or 2 beep as everyone I work with calls 'em) is necessary, but if the cue isn't leaving the digital domain just include the timecode number as part of the file. That said, excellent tutorial.


Hi ST,


Couple of things...


Re the nomenclature, I learned the term as "2-pop". I guess we now know they can also be called 2-beeps too. Thanks!


[NOTE: re-reading this post now 7 years later, and the following is no longer relevant] -- when it comes to scoring in Logic, I've found that my movie start time must always be adjusted at least .5 frame in one direction or the other in order to get a movie's t/c burn line to align exactly with Logic's t/c counter, particularly at the beginning of a clip or reel. Sometimes it's .5 frame early, sometimes 60 bits early, sometimes late, and on the latest film mix I did the offset for the movie start time needed to be an entire frame later.


This must have something to do with the codec used to encode each different movie or something else that I'm not aware of. In any event, I don't know that when working even with a Logic-supported frame rate how this would affect a BWV time stamp. So for me, delivering popped audio files is the method that provides the least amount of guesswork for alignment.



I've yet to work on a project that was tape based. All of my scoring gigs have been digital, running the gamut from inexperienced indy to some "name" film companies. I've found that the pops are helpful when dealing with first-time filmmakers. For established film companies & editors there's an expectation to deliver popped files. So I pop!


Anyway, glad you liked the tutorial. Hopefully there will be a day when pops are rendered totally antiquated, because there are always a few times when the volume's up and a pop goes by that's loud enough to blow my hat off. I'm sure you know what I mean :D





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  • 6 years later...

Thanks for sharing all this Ski, really helpful.


I'm just doing my first (short) movie score and there is no timecode on the picture. Is this why the sound editor has asked me to place a pop 2 secs before the PICTURE starts?


This created a tricky situation as I'd scored the whole thing with the movie starting at 1111, and luckily I read the thread about Logic bugs in the negative bar numbers, as I was planning to drag the start position back and put the pop at 00:59:58:00:00. Looks like I will be exporting stems to a blank project and starting them 2 seconds in!

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You're welcome!


It's too bad you're having to score this without timecode. But be that as it may... I think he wants a 2-pop to ensure that all of your stems start at the same place (he'll likely align them visually) and also to ensure sync. But if possible, ask the editor to send you a cut of the film with timecode striped from the very top. That will eliminate all guesswork. The trick is to get him to send you an exact copy of what you're working on, just with a timecode "overlay" onto the video. Then you can swap out the new picture for the old one and everything will line up.


If you can't get that, then my first thought was this: hopefully the film doesn't start with a fade up from black! If it starts hard with picture then figuring out the proper point to place your 2-pop should be easy even without timecode.

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Haha... yes... the film starts with a black screen and in silence! My first thought was 'can I trust that the beginning of the movie file is going to be the first frame of the picture?' I have to hope that it is, and be as accurate as I can!


Thanks for the advice :-)

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It's entirely possible that the sound editor doesn't know exactly why he/she needs a 2-pop, except that they're aware that these things are used to ensure sync on some level. I had a student film once where they could not or would not give me time code (although I requested it) so I resorted to simply bouncing everything, no matter how far into the film, from the start and crossing my fingers. Even at that, the editor moved things around to suit her own purposes and my finely timed entries went out the window!


But as ski mentioned, it might simply be to make sure all your stems line up.

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  • 2 weeks later...

The sound editor has just asked the fllmaker for a 2 pop as well, so I'll put my stems on that new version of the film and line my pops up with the film's.


The sound editor is the most experienced among us, I've never done screen before and he's worked in Hollywood for years, so I'm just going to do what he asks for!

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