When recording interviews you should pay special attention to the sound quality. Use professional directional microphones such as condenser microphones when available. Connect them to the camera or an external audio recorder. If you use an external recorder, notice you need to synchronize the shots and your recordings later on. In lightweight productions it is usually a better idea to connect straight to the camera. Remember to use manual audio settings as the cameras auto gain might result in waving audio levels in some cases.
It is important to get as clean sound as possible. To do this, you should minimize the background noise such as ventilation, sounds from traffic etc. Pay attention to the room echo! It’s better to record in a room with something soft in it to minimize the echo. Remember to place the microphones close to the speaker (about one meter distance is optimal) and always monitor the recorded sound with headphones!
The result of audio levels going too high is called clipping. When digital audio clips it is hard to recover without costly professional post-production equipment.
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