How important is quality sound to your video?  If you’re recording a webinar and charging a sponsor $40,000, it had better be perfect, but “man on the street” interviews won’t suffer from a little background noise.  Just about any microphone can get the job done, but there are real advantages to having the right microphone for a particular situation. Here’s how to choose:

Casual, close-quarters video:  Use the camcorder microphone

A lot of great video has been taken with just a camcorder and the microphone built into it.  If you’re going to get in close (5 feet or less) to your subject and don’t need studio quality, the sound will likely be just fine.  Not having to juggle external mics may even let you capture something you otherwise wouldn’t have time to react to.

Video in noisy places:  Use a “close” microphone

Interviews at trade shows, in offices, or anywhere you can’t control ambient noise you’ll want a “close” microphone, one that’s designed to be held very close to the sound source.  Close mics feature the best ambient noise reduction, best clarity of voice and most reliable audio level.  Just take a look at the news and you’ll see that everyone either has a lavaliere mic, a handheld mic or both.

On a Hollywood set, you’ll see a guy hanging out with a boom mic just off camera, trying to keep that shotgun microphone as close as possible without getting in frame, but in post production, that audio is only used for reference while they do dialog replacement with a close mic on a soundstage.  Even Broadway has abandoned stage mics in favor of body mics (lavaliere mics taped at the hairline).

Lavaliere or handheld microphones are generally omnidirectional, and will pick up sound in a 3′ bubble around the subject’s head. If the mic is set up right, it won’t pick up background noise.

Video in fast-moving, unpredictable situations:  Use a shotgun microphone

An argument could be made that if you can only afford one microphone, a shotgun is a decent utility player. If you don’t have the time or opportunity to put a mic on your subject, a shotgun microphone gives you a lot more useful range (10’ – 30’) and flexibility than your camcorder’s built-in microphone.

A shotgun (or any cardioid to hyper-cardioid, “directional” mic) makes a compromise to let you record from a distance by exaggerating the pickup pattern along one axis, but it can’t reject the other directions completely. You will likely pick up some background noise.  I wouldn’t buy a shotgun microphone for less than $300 to $500–enough to get you into a Beyer or Audio Technica and out of the mass-market products.

Video in a controlled studio environment:  Use a “close” microphone

If you’re in a studio, or have a “set” where subjects sit in pre-determined spots, a wired lavaliere or stand-mounted microphone will deliver excellent sound at a lower cost than a comparable wireless mic.  However, even in studios, it’s sometimes convenient to use a wireless lavaliere microphone so you don’t have to worry about hiding or tripping over wires.

Video of a roundtable discussion:  Use close microphones with a mixer

You can get away with passing a handheld mic around, but you’ll kill the flow of the conversation between your panel members.  Instead, equip everyone with wireless lavaliere microphones.  You’ll need a mixer that allows you to record all of those signals to your camcorder.  If you produce this kind of video regularly, you need technical information beyond the scope of this article.  This article on the B&H Photo site goes into the kind of technical considerations you’ll need.  Otherwise, many places rent equipment like this.  Just be sure you get thoroughly trained on setting up and using any rental equipment before you leave the store.

Video blogs or podcasts:  Use a desktop USB microphone

Most people use their computer’s built-in microphone (and camera) for this, but if you want the final product to stand out, sound quality will help a lot.  Poor sound screams “amateur” just as loudly as poor lighting. There are several quality desktop microphones available with a USB connector so they can be plugged right into your computer, and they are pretty inexpensive.

Wired vs. wireless

Unless you’re setting up a dedicated video studio, you’ll find wireless lavaliere or handheld microphones far more convenient than wired microphones. Capturing quality video, especially in the field, is not easy, so we value anything that shortens the path to a quality product.  Wrangling wires on location is one obstacle that’s easily eliminated.

Best case:  Have the right mic for every job

If you produce a lot of video under varying conditions, it’s smart to have several microphones so that you can use the right tool for each job.  Don’t skimp on quality if you’re planning to make money from your video.  Read instructions and practice with any new equipment several times before you have to use it for real.

Microphone resources

A store that stocks a large selection of professional audio and video equipment will likely have staff who understand that equipment and can guide you to a good choice.  I purchased our wireless Sennheiser Evolution G2 at B&H Photo here in Manhattan and got excellent advice and instruction from the staff there.  You can get a great price on nearly any microphone on Amazon, but I’d strongly advise you to have a face-to-face conversation with an expert instead.

Microphone placement and other video techniques from the Knight Digital Media Center: http://multimedia.journalism.berkeley.edu/tutorials/shooting_tips/microphones/

More in-depth articles on choosing microphones and audio for video from Videomaker magazine: http://www.videomaker.com/learn/production/audio/microphones/