Mediaworks - DSLR Dual System Sound

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Dual system sound is a motion picture technique of capturing sound on a separate device from the camera. The image and the soundtrack are synchronized during post-production using sync points that are typically accomplished using a clapper board.

It is critical that:

  • A sync point, or marker, is clearly captured both visually and audibly at either the beginning or end of each recording
  • Both recording devices are using compatible record settings


Use only the T2i model Canon Rebel

  • Record Format > 1920x1080 (30 fps)
  • Sound Recording > On (it is recommended to record a scratch audio track. There is a known issue of the camera audio being out of sync)


Zoom Recorders

Record Format

  • 48 kHz / 24 bit -highest quality
  • 48 kHz / 16 bit


  • Lavalier
    • Most are omni-directional, a few are cardioid.
    • Good for interviews.
  • Shotgun
    • Use a boom.
    • Check for bass roll-off on mic.
    • Use a wind screen when outside.


  • There needs to be an audio and visual sync point at the beginning or end of each clip.
  • Use a clapperboard or clap your hands.
  • On the clapperboard write the production name, scene, shot, and take.

Head Slate

  1. Director or AD calls for "quiet on the set" and then for "roll sound".
  2. The sound engineer will start recording and allow a few seconds of pre-roll before calling out "speed".
  3. The camera operator will commence recording and call out "speed".
  4. The AC will be holding the slate that is clearly labeled with scene information in front of the camera and the clapper sticks open. The AC will verbally state the slate information and call "marker" and close the sticks while holding this pose for a few seconds.

Tail Slate

If a slate is not possible at the start of the take it can happen at the end

  1. After the Director calls "cut" both the sound engineer and camera operator should let the recording continue.
  2. The AC should complete the slate calls in the reverse order and hold the clapper upside down to signify this is a tail slate.


Prepare audio clips by normalizing in Peak and saving an appropriately named track that will be easily identifiable with the corresponding video clip.

Note: When normalizing select the portion of audio after the clap marker.

If the audio files are stereo buy there is only audio on one track they can be converted to mono.

  1. Open the file.
  2. Go to Edit > Select All.
  3. Go to DSP > Stereo to Mono.
  4. In the new window set the slider to the left or right depending on which side you need to keep.

Final Cut

Remember that it is easier to rename the files (if needed) before they are imported to Final Cut.

Importing Files

  • Import the audio files into a Bin.

Merging Clips

Follow the article below for instructions on syncing the audio and video files with the Merge Clips command.

Exif Data

Read this article for Exif Data information.