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Im about to embark on a indie feature road trip movie. This story thrives on improvisation with characters and "real life" people. What kind of tricks do you know that could help get the cleanest audio for this kind of project?
Things like mic'ing an actor with the intention of recording another subject off the mic. Planting mics on nearby props/set dec. Etc.???
ps- i understand the legal ramifications of going about things this way...but thats what the producers are here for.
Depending on what the actors are wearing, you might consider hiding a lavalier mic in plain sight on each actor's body. There are some awesome techniques for doing this, like the PEN CAP TRICK (starts at 3:28), replacing a button or other part of the garment with the mic, or using something like the RODE PINMIC on a similarly-colored garment. All of these tricks keep the cable of the mic hidden and give you a clear shot between the mic and the passerby's voice. Plus, both the pinmic and the pen cap trick very effectively prevent clothing from rustling against the mic element.
No matter what technique/mic you use, make sure that whatever recorder you use on has a low noise floor and has some form of limiter built-in to the input. You'll likely be doing a lot of mixing between the loud presence of the actor's voice and the distant softness of the passerby, and you'll feel much more comfortable having the protection of a limiter.
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May seem a very obvious point, but if using lav mics (hidden or not) make sure to use omnidirectional mics such as DPA 4060/4061 or Sanken COS-11. This will increase your chances of capturing off-axis content.