Hi there! Yes, it's pretty standard to have a separate sound recording. Synchronizing video and audio is what the slate (the clapboard with the scene and take written on it) is for. You align the sound of the closing of the slate with the visual of the instant the slate is closed. Since most cameras record audio at the same time, this is helpful but not 100% necessary. With the audio built into the camera most professional grade video editing software has the ability to synchronize separately recorded audio with the camera's audio. Often it's as easy as selecting both the audio file and video file and choosing the function in the program that synchronizes them (usually called something like synch)

Sean Mannion
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Founder, 4MileCircus (?url? http://4milecircus.com?/url?)
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