16 Replies Latest reply on Jan 24, 2011 12:41 PM by BillyBRoll

    Aligning Video Clips to Audio


      I have searched these forums as well as others without much luck.  I  am recording audio on a Zoom H4n and using a Canon 5dmkii for video. When shooting a sequence, I start the audio and can use the clapboard method to sync at the beginning.  My problem is that as I stop recording video to refocus or change position, I have a hard time aligning the subsequent video clips to the constantly running audio from the Zoom.  Does anyone have tips or a link to a tutorial that may offer advice on this?  Thanks in advance!



        • 1. Re: Aligning Video Clips to Audio
          Jim_Simon Level 8

          Every time you stop the camera, you also stop the audio.  "Cut" applies to the action, camera and sound recordist.


          Every time you restart the camera, you also restart the audio, and do another clap.

          • 2. Re: Aligning Video Clips to Audio
            Colin Brougham Level 6

            As long as you used the clapboard at the beginning of each video recording, you're fine.


            Drop the Zoom audio into the sequence. Swivel the track down so you can see the waveform; you should be able to see the brief transients/peaks of the clapboard sound.


            Load your first clip into the Source Monitor, and move the CTI to the frame where the clapper comes down; mark an In point. Move the CTI in the sequence to the first peak, and edit the clip into the sequence. Repeat this for all clips. When you're done, use the razor to split the audio clip into pieces matching your video; you can then link the audio to the video, so that they stay together.


            But if you didn't use the clapboard everytime... well.. that's going to take some more work I've got an idea but I'll let you respond first.

            • 3. Re: Aligning Video Clips to Audio
              pm987 Level 1

              Thanks to both of you for the prompt responses, I appreciate it! I should better explain the circumstance I'm referring to. Suppose I'm shooting a dialogue between 2 people with one camera.  I want the audio to be nonstop in the final and stop video to refocus or change subject (the holes in the video will be filled with other footage while the audio of the conversation plays beneath.)  I hope that makes sense, and thanks again for any help.



              • 4. Re: Aligning Video Clips to Audio
                Colin Brougham Level 6
                I hope that makes sense...


                Umm... guess I'm not sure I'm following. When you say "stop video" are you referring to stopping recording, or do you mean you rolled through the focus/shot changes and now you want to replace that video with something else? I'm sure you're referring to something simple here, but I'm having a hard time grasping it at the moment... sorry


                If you can outline in a little more detail what you're dealing with from a footage standpoint, and then what you're hoping to accomplish, that will help.

                • 5. Re: Aligning Video Clips to Audio
                  Jim_Simon Level 8
                  I hope that makes sense


                  The final result does.  The method of achieving it does not.


                  When the camera stops, the action and sound stop as well.  Wait until the camera and sound are rolling again before you continue the action.  "Clap" first.


                  For a two person dialog, you'll want a minimum of three position coverage.  Over A's shoulder looking at B, over B's shoulder looking at A, and a two-shot of A and B in the frame. (You may want more, but those three are a good minimum.)  For each take, the actors run thorugh the entire dialog.


                  For B-roll coverage (actors are speaking but not on screen), recording sound won't matter.


                  All that footage and all those takes are then edited into a "continuous" whole.

                  • 6. Re: Aligning Video Clips to Audio
                    pm987 Level 1

                    Okay, I think I understand what you're saying.  How about situations that aren;t scrtipted and you're just capturing a dialogue that's taking place.  In those situations (when rerecording the whole several times to get the necessary positions is not possible) are you saying (as the others seem to have stated) to roll thorough the changes without stopping recording?  Or is there a way to stop recording video, refocus/change position, and start recording, then sync those clips to the audio, separately recorded in its entirety?  I'm very new to video so thank you all for bearing with me!



                    • 7. Re: Aligning Video Clips to Audio
                      shooternz Level 6

                      I think that the Zoom will record a form of Free run TC


                      Set your camera to do the same. ( Hopefully it has the capabilty to record FREE RUN TC *)


                      Establish if there is an off-set between camera and zoom by a simple test sequence and memorise that.


                      This makes it easy to align in a timeline.


                      Only remaining issue...do the two devices stay in synch over time.



                      * If your camera can not do this ...you are using the wrong tools for what you are doing.

                      • 8. Re: Aligning Video Clips to Audio
                        the_wine_snob Level 9



                        In those cases, you will want to think about cut-aways, and L, or J-Cuts. Just keep the Zoom going, and plan on how you will fill the missing Video. Here, cut-aways work well, so shoot some of those, with plans on using them in the main Video. For J & L-Cuts, this ARTICLE might be helpful. For general syncing, this ARTICLE has some tips on the mechanics.


                        Always shoot plenty of cut-away footage, say the back of the interviewer's head, looking at the interviewee, but not with such an angle that one can see what the interviewee is saying. Look for "show-and-tell" objects/subjects, that can fill the time, or think about graphics - charts-n-graphs, etc.


                        Good luck,



                        1 person found this helpful
                        • 9. Re: Aligning Video Clips to Audio
                          Colin Brougham Level 6

                          Well, look at it this way: you're standing between two people having a conversation. Person A says something while you're looking at him. Then, Person B responds, and you turn to look at her. Unless you can warp time and space, you're not going to see the first few moments of her remarks. You'll hear them, but you won't see them. The same happens when you're recording with a single camera and audio recorder, because vision is directional whereas hearing--generally speaking--is not.


                          If you're recording spontaneous dialogue, e.g. for a documentary, then you really only have a couple options: shoot with more than one camera simultaneously, or shoot firehose video. This is when you spray the camera back and forth like a crazy person to try and catch the person talking. Yep, it looks just about as good as it sounds, but sometimes it works.


                          The other option, if you have only one camera and the time and the shooting scenario allows it, is to shoot everything from one angle, and then shoot the same thing from another angle. Then, once you sync up your audio and video, you edit back and forth between the two--multicamera editing works great, here. This is how pretty much all movies and TV dramas would be shot and produced.


                          We can bend time in production, but only so far

                          1 person found this helpful
                          • 10. Re: Aligning Video Clips to Audio
                            davidbeisner2010 Level 3

                            I'd agree with the other advice you've received here... Two options to fix your problem.


                            1. If you're covering the "gaps" with b-roll but still want your sound running, just keep both camera and audio running while you make your changes. If you're putting b-roll there, you'll never see the crap that comes when you change your camera around anyway... just be sure you've got b-roll available for your camera move!
                            2. This one is easier on your editor--he doesn't have to have b-roll to cover things... use the free-run time code option that was suggested above by Shooter... At the beginning of your shoot, reset timecode on your zoom and your camera to 0 and then set it to do free-run timecode. That way your video and audio timecode will always match up and you can sync them later based on timecode. One note on this, make sure your audio speed matches the framerate of your video--often with third party audio recorders that aren't designed specifically for video, they'll record at an audio rate that doesn't match your video. You can usually fix it using the "interpret footage" command on your audio, but it doesn't always give you clean results.


                            Good luck!

                            • 11. Re: Aligning Video Clips to Audio
                              davidbeisner2010 Level 3

                              Actually, I just thought of something that will make things difficult for you in the first option given there... the 5DMKII has a max record run time of 12 minutes (part of why that camera's not ready for the broad use its getting in the video industry!) and so allowing your camera to continue running while you do moves could be an issue. And you'll have to stop every 12 minutes to change cards, meaning that you'll end up with having to resync your audio/video manually every 12 minutes. So if your camera and Zoom both support the free-run TC, that's your best option.

                              • 12. Re: Aligning Video Clips to Audio
                                Jim_Simon Level 8
                                How about situations that aren;t scrtipted and you're just capturing a dialogue that's taking place.


                                Is such "live" situations, bring multiple cameras.  One looking over A's shoulder at B, one looking over B's shoulder at A, and one with both A and B in the frame.  As before, B-roll footage won't need sound.

                                • 13. Re: Aligning Video Clips to Audio
                                  Jim_Simon Level 8

                                  * If your camera can not do this ...you are using the wrong tools for what you are doing.


                                  Cameras do it without issue.  It's the (affordable) digital audio recorders that have a hard time with standard clock speeds.

                                  • 14. Re: Aligning Video Clips to Audio
                                    Colin Brougham-u9E3Ff Level 1

                                    DSLRs--at least the current crop--don't record timecode, free-run or otherwise. All clips start at 00:00:00:00. You can sync video and audio visually and manually if you have a clapboard, or use PluralEyes to sync semi-automatically, so long as you have audio with the video. The producer I edit for does this with his T2i and Zoom. He's got a small shotgun on the T2i which helps pick up decent levels and make syncing better.

                                    • 15. Re: Aligning Video Clips to Audio
                                      pm987 Level 1

                                      Just downloaded the trial for PluralEyes and this is exactly what I was looking for.  Thanks to everyone who answered, I learned from each of you and greatly appreciate all the help.



                                      • 16. Re: Aligning Video Clips to Audio
                                        BillyBRoll Level 1

                                        +1 on Plural Eyes. It is a very valuable piece of software. However, be careful not to get into your project using a lot of effects that Final Cut may not like since in Premiere it is exported as a Final Cut file. Even though you could open up the xml in Final Cut and just work around the missing effects, the exported sequence now has an error attached to it letting you know of the effects used in Premeriere that won't be used in Final Cut. For some reason when this message is attached to the xml file, it will not open up in Plural Eyes. So, the best thing to do is to sync first with all of your assets in the timeline to create a new sequence then do the work. One really cool feature is the replace audio which is nice if you are going cut video clips and move them around with the good audio attached to the clips.