On this interesting video David Day from Adorama takes a look at two ways to record sound for videos – a lav mic and a boom mic and what are the advantages and disadvantages of both methods.
Both lavalier mics and boom mics can be very useful for recording sound when you shoot a video, interview or a movie, however you need to understand how they work in order to choose which one fits your specific use case.
Let’s start with a lavalier mic – these are small, light and are physically connected to your talent so you don’t have to use an operator to follow the talent as he or she moves in the shot. On the downside you might not always like to place them on the outside of your talent’s clothing as they are visible (you will never see a lav mic in a movie production for example as this will not look “natural”). They also have a very specific sound which is very directional and you might actually want to capture a bit more of the ambience of the room or sounding.
The other option is of course a boom mic. These are larger and typically mounted on… a boom (yes, surprise surprise). Although you can hold the boom poll on a stand (light stand or C-stand), if your talent is not sitting in a fixed position facing a single direction all the time – you will need a boom operator to hold the boom above your talent and make sure the boom mic is always close to the person talking in the direction of his mouth.
Another issue with a boom mic is that if you are not careful it can get into the shot (many TV shows have accidental boom mics showing in one time or another), also if you have an open wide shot it might be very difficult to use a boom mic (this is also true for when you might be shooting in a very narrow space and don’t have the option to squeeze in a boom mic). In these cases, as well as a few others a lavalier mic is the only option, while in other cases you can mix the to for optimal results.
On LensVid we have a very extensive section devoted to sound recording for video productions which covers both equipment and techniques here on LensVid as well as a channel dedicated to photography gear guides.