When you get a Blackmagic Pocket Cinema Camera 4K there are three microphone options: built in stereo microphones, a 3.5mm jack input, and a mini-XLR input — which can also provide power. The later BMPCC models have an extra mini-XLR input. Let's take a look at how you can choose when to use each of your options.
Microphones and the Blackmagic Pocket Cinema Camera
If you use the inbuilt microphones, they’re actually not too bad for what they are. There’s one on the left channel one on right channel, so they provide a stereo audio image – in effect, a stereo microphone. They don’t have much in the way of wind resistance, that can be an issue when you’re filming outside. They’re okay for scratch audio for synching later if you’re using an external recorder… and that’s about it really. All in all they’re not the best way to record audio if you want a professional result.
3.5mm Input Jack
If you wanted to use an external stereo mic in place of the built-in stereo microphone, you can use the 3.5mm input with left and right assigned to the appropriate channels via the audio jack.
Lavalier (Lav) Microphones
These are microphones that you clip directly to someone. When connecting them to the PCC, there are some lav mics that you can plug directly into the audio jack, on a long cable, or you can plug in a wireless receiver, into either the mini-XLR or the jack, and then the receiver will pick up the signal from the corresponding lav mic on an interview subject. This requires a different setting in the camera but again that’s something we’ll go into in another article.
Lav microphones are great for closeup vocal recording. One downside is that they capture very little room sound/ambience and you might want some of that, but you can always record it separately and add it in post.
Adding a windsock is essential for any outdoor recording, the slightest bit of wind and you’re really going to hear that. A wireless lav mic is ideal if your subject is moving around and especially useful if you’re a solo filmmaker and you don’t have a dedicated sound tech with you to follow someone around with a shotgun.
What to Look for and Consider When Choosing a Lav Mic
Buy cheap, pay twice: go for a mic that’s at the top-end of your budget or you’ll end up replacing it later. It’s often better to go with a known and trusted brand with a good reputation for quality audio, like Rode or Sennheiser.
Lav mics are delicate, and people quite often forget they have one attached and wander off with them, so remember to keep an eye on yours and also to make sure your subject clips the transmitter securely or puts it in a pocket; more people than you’d believe stand up and drag the transmitter with them, bashing it off the floor. It’s worth buying extra mic clips too, as they have a tendency to ping off and get lost easily.
Despite what the name suggets, "shotgun" microphones are the opposite of a scattershot; they are highly directional microphones that come in a variety of capture patterns. Primarily they’re designed to record what is in front of them, cancelling side noise as much as possible. Having said that, unlike lav mics, you do capture more room tone with a shotgun.
They’re great for use on boom poles, say if you were recording actors or presenters and didn’t want to have to hide microphones in clothing. They can be handheld, like by news reporters, though ideally with an appropriate shock mount so you don’t get a hand rustling noise. They're essential at helping you keep your distance from the person speaking. They’re also good for fast turnovers if you don’t have time to mic someone up, like a news reporter doorstepping a politician for example.
You can get shotgun mics that go into the 3.5mm jack, but as most shotgun mics need a power supply. Some come with batteries, or you can go through an external phantom power source, like a mixer. If you put the shotgun in the mini-XLR you’ll probably need a mini-to-regular XLR convertor cable, which is a short lead that takes the small input from the camera to the larger output of the mic – we leave ours permanently plugged into the camera as with the Blackmagic Pocket Cinema Camera, you ideally don’t want to pull stuff in and out of the camera all the time.
If you’re using the mini-XLR input you can use mics that either need power, which the camera will then provide, don’t need power, or have their own power. If a mic has its own power, you need to set the camera settings to make sure it doesn’t also try to power the mic via phantom power, otherwise you can blow it. So if you have a self-powered mic or an unpowered mic (one that doesn’t require power at all) don’t send it any power, remember to double check in the menu settings whether phantom power is on or off.
What to Look for and Consider When Choosing a Shotgun Mic
When choosing one, looking at frequency response is important, and if you want a nice tone you’ll pay for it. As with lav mics, your safest bet is well-known brands with a good reputation. Shotguns can vary quite a bit in size so you’ll need to make sure you can fit it into kit bags and transport it easily. You also need a sock/dead cat/blimp if you’re outdoors to reduce wind noise.
On-Camera Shotgun Mic
A short, portable shotgun mic mounted on the camera can be a good back up and source for quality scratch audio, for syncing and room tone. If that’s all you’re using it for then you can go a bit cheaper than you would with a shotgun intended to capture professional audio, but if you still want it to record good quality sound then you’ll need to give consideration to that in the same way as the ‘shotgun’ section above.
Just for scratch and backup, you can get a microphone that doesn’t require any power. It’ll take up the 3.5mm Jack socket in the case of BMPCC, but for professional audio you’d likely be using the mini-XLR anyway.
Attaching microphones to the BMPCC is difficult unless you’ve invested in an external cage as the BMPCC out of the box has no shoe attachments at all. You can screw a cold shoe into the body of the camera, or you can attach a cage, or handle, and then mount the microphone to that. Most cages and handles come with cold shoe slots.
After that, it depends what microphone you want to attach, but likely you’d be mounting some form of shotgun mic and ideally, you’d want a shock mount or vibration absorbing mount to reduce unwanted noise picking up.
More Blackmagic Pocket Cinema Camera Resources
And that's the basics! For more on using microphones with your camera, try David Bode's course about On Camera Sound for Solo Video Producers. Here are more free tutorials to help you use your camera.