When video crews want to record someone talking with clear sound they often use a dead cat. It’s nothing to worry about as “dead cat” is the term for a furry shield around a microphone to keep the wind out. Usually they put it around the microphone, which is put on a stick which is hovered above the filming scene.
But likely you don’t want to use any sound guys, and you want to keep your cat alive. So how to get good sound?
The dead cat is to combat one of the three enemies of recording sound: wind. The other two are distance and your own ears.
Even a slight wind breeze that blows into a microphone (hand-held, or the one built into your camera) will always lead to much more noise than you think. it will become hard to understand what people are saying. Therefore it’s always good to try keep out of the wind. Sometimes just turning your back to the wind direction can already help. that’s not always easy, because the light situation also changes when turning, so you need to balance that. When using a real microphone, any cloth (or indeed a “dead cat”) around it will muffle the sound a bit, but that is preferable to having the wind rumble.
Second enemy of sound is distance. especially on noisy race tracks it’s essential to be as close to your talking person as possible. Every centimeter counts! The sound level decreases exponential when going further away. At the same time environment noise gets worse. If you can attach an external microphone to your camera, always use that option. That way you can put the microphone nearby your ‘talker’ and still film from further away,. it gives you much greater control and, even with a cheap microphone, a much clearer sound. My trick is actually to use a not-sensitive microphone (so it doesn’t record much from the environment) but keep it just a few cm from the speaker (so the voice is still clear). Close enough for good voice, “non-sensitive” enough to not let through much environment noise.
The third challenge: your ears. You can never believe what you hear. Your ears and brain work together as a great noise filter, masking sounds you don’t ‘need’. But they only do this well ‘live’. Once you listen to something that’s recorded, it’s much more difficult for your ears and brain to filter out that aircon hum, some music playing from far away speakers, or a roar from a passing car. Try to stay away from any noise sources, even if they sound not so loud to you. If possible with your camera, use headphones during recording, then you already get a much better idea of what you really record.
There is a lot more to say about sound, but for now, stay close to your talker, away from noise. Use a microphone if possible! Happy filming!