Just like cameras, there is no single recorder that’s perfect for every production; however, you can enhance your camera’s capabilities with a recorder that fills in the gaps.
On some projects, you can mask problems with your picture in post production with alterations in color and contrast, making them look like stylistic choices; however, you usually can’t do that with audio. You might be able to ADR (additional audio recording) all the dialog of your short film in post, but it’s not likely that the bride and groom are going to want to re-record their wedding vows after you’ve done the shoot for them. In some cases, there simply is no alternative to professional quality production sound.
Most cameras don’t offer all the features needed to ensure that you can get good quality sound for your production. This is where an external recorder can give you the ability to capture great sound, either with better input and output jacks, a lower noise floor, higher audio sample rates and bit depth, or by offering more control to adapt to the recording environment.
1/8-inch vs. XLR Jacks
Just because an audio signal passes through an XLR jack, it doesn’t make it better quality; however, using XLR cables and jacks can help eliminate some common problems with audio signal flow in production. Reliability is very important for signal flow. XLR connections lock in place; most 1/8-inch connections do not and can easily come out. Most equipment using XLR jacks use grounded connections to help eliminate RF noise in the signal; most 1/8-inch jacks don’t allow for grounded connections. During a production, the size of XLR jacks make them more durable and less likely to break in contrast to smaller 1/8-inch connections. As an added bonus, XLR inputs usually can provide the phantom power needed by many professional microphones.
Noise Floor and Audio Formats
All audio recorders have a noise floor. When you start a recording with no microphone attached or enabled, what you will hear in the recording is that noise floor. Generally, the better a recording device is designed and built, the lower the noise floor will be. Many cameras and recorders don’t list audio noise floor information in their specs, but this is certainly something you can learn by doing test recordings with the equipment before you shoot.
If you want great audio, you’re going to need to record in WAV or another uncompressed format. Unlike recording compressed images, recording compressed audio severely limits what you can do in post. Of course, if your only delivery is a live web stream, then recording compressed audio may be fine; but you should test your workflow just to be sure.
Unlike recording compressed images, recording compressed audio severely limits what you can do in post.
Changing your record format from 16bit/48khz to 24bit /96khz WAV may not give you a noticeable difference in sound quality. However, what it will do is give your audio signal more information, making it easier to make alterations like noise reduction and equalization, often providing noticeably higher quality sound at the end of post.
Ergonomics and Isolation
Beyond boom poles, we don’t hear much about the ergonomics of working with audio equipment on a shoot, but this can greatly affect the sound you’re recording. You’ll find that the easier the gear is to operate, the more consistent your results will be. Having gain controls that are physical rather than menu based and can be quickly and easily adjusted will help you maintain proper audio levels. Using an audio recorder that is separate from your camera rig will eliminate the risk of vibrating the camera while adjusting gain. Likewise, if your audio gear is separate from your camera rig, you’re less likely to pick up camera noise in your audio recordings.
Video Recorders: Color and Formats
Many cameras only record in 4:2:0 chroma subsampling, which can lead to some images having color that looks a little off. 4:2:2 subsampling has four times as much color information as 4:2:0 color and gives you color that looks almost exactly like full bandwidth color (4:4:4). Many recorders support 4:2:0 color via HDMI and 4:4:4 color via SDI.
At times, because of a client’s needs or to streamline your own post-production workflow, you may need to record in a specific format like ProRes 422 or DNxHR HQx to work more easily with editing software like FCP or Media Composer. Recorders often support these formats while many cameras don’t.
Screen Size, Resolution, and Brightness
Onboard camera monitors are typically small, low res and not very bright. There are many monitor/recorders with 5-inch to 7-inch screens in HD resolutions (720, 1080); some are even bright enough to see in sunlight.
Sound Recordist/Audio Engineer
Until AI gets a lot cheaper and better, there is no substitute for a crew member dedicated solely to recording great sound. A camera recording without an operator won’t always get you the greatest of pictures; the same is true for audio. That said, on many productions it just isn’t possible to have a separate sound crew. There are, however, some workarounds that can get you really good results.
Solutions For Your Shoot
Let’s take a look at some common production needs you may experience in the field. We’ll match these with techniques and gear choices that will help you along with the process.
Wireless lavs won’t work, but you need to mic the talent
Because the airwaves are becoming more and more crowded, finding good frequencies for wireless microphones can be challenging. It can also be just as difficult when you don’t have the budget for wireless kits. This is where the Zoom F1 ($200) or Tascam DR-10 ($200) can help. Both of these recorders come with lavalier mics and look a lot like wireless mic transmitters; however, the belt packs record to microSD cards in 24bit/96k Broadcast WAV. This allows you to mic your talent and let them go and get 10 hours of recording from 2 AAA batteries. The Tascam has the advantage of allowing you to record to two tracks at different gain levels so you can adjust one channel normally and have the second at a lower level; so, even if the talent screams, you’ll have a clean recording on that track. The Zoom F1 has the advantage of working with a selection of different microphones from Zoom, making the unit more versatile.
Monitoring the audio recording is necessary, but you can’t run a cable
There are times when the recorder can’t be attached to the camera, but you still need to listen to the audio of your recording. With the Roland R-07 ($230), you can pair a set of Bluetooth headphones to the recorder and monitor your audio up to 30 feet away. If you patched into a mixing board at a live event, you could monitor your audio recording wirelessly.
You need to mic the talent but you also need to hear the surroundings
Shotgun mics and lavaliers are often designed to be very directional; so, often the only thing you’ll hear is the person who is mic’d. This is great but if the talent is in a noisy location, it’s going to sound odd if you can’t hear any background noise at all. With a recorder like the Tascam DR-40 ($180) or the Zoom H4n Pro ($200) you can record two mics via XLR; additionally, the recorders have two onboard mics that are great for recording ambient sound to two additional separate tracks. This allows you to mix the four tracks together in post to get just the right amount of background sound.
You need better quality recordings for your green screen shots
Even when you’re in 4K, recording in 4:2:0 color and then pulling a chroma key from your green screen footage can be very difficult. The Blackmagic Design Video Assist 4K ($895) can record 4:2:2 color in UHD from its HDMI or SDI inputs. This makes it compatible with most cameras on the market. Also, it has a 1920 x 1080 7-inch screen and supports recording in ProRes and DNx codecs.
The LCD screen on your camera is too dark to see outside
Most cameras have screens that are challenging to view in full daylight outdoors. They often have a brightness of around 300 to 500 candela per square metre (cd/m²). The Atomos Ninja V ($695) has a 1000 cd/m², 1920 x 1200, 5-inch screen that is easy to see outdoors. It can record 4K at 60 frames per second in a variety of log formats, and it supports HDR.
You want to shoot DCI 4K in raw for your film
Most cameras don’t allow you to record in raw format, but raw is often desirable because it gives you all the data produced by the image sensor to provide the most latitude and help preserve your image quality for post. The Atomos Shogun Inferno ($1,295) supports DCI 4K resolution (4096 x 2160) in the raw format of many popular cameras. It also has a 1500 cd/m², 7-inch screen as well as HDMI and SDI inputs.
Three mics need to be recorded in sync with the video
Most cameras have only two XLR inputs, if they have any at all. Syncing audio and video records in post is a tedious task. With a recorder like the Sound Devices MixPre-3 ($649) or the Tascam DR-701D ($450), you can patch in three mics (four with the DR-701D) and take the HDMI output of your camera to keep the audio in sync with the video. You will want to check manufacturers websites for compatible cameras. One should also note that the DR-701D also has a BNC input for timecode.
You have to record a four-mic acoustic music set
Acoustic instruments, like guitars and violins, are known for producing very subtle tones. In order to get a clean recording, you’ll need a recorder with a low noise floor. While most professional recorders don’t have very high noise floors, the Zoom F4 ($560) boasts a -127 dBu EIN, which is a noise floor of about 1 dBu over the theoretical minimum. This means you won’t have to worry about the recorder adding noise to your tracks.
Record and switch between three camera shots with one camera
Live events can be tough. There often isn’t the time, space or budget to setup multiple cameras. The Convergent Design Odyssey 7Q+ ($1,495) can help solve that problem. It allows you to capture one UHD (4K) input and record it in HD, while recording two other HD windows (¼ frame) from the same UHD input. The Q7+ even allows you to switch between those three shots while recording that switch and outputting it via SDI. So if you have your camera set with a wide shot of two people seated across from each other, you can position those two windows as single shots of each person while recording a switch between all three shots. You can send that output to a large monitor or to a web stream.
Summing It Up
Production has its challenges, but with the right tools the work is a lot easier. Audio and video recorders can help fill some of the needs when your camera falls short. They can also make your job a bit more comfortable.
Odin Lindblom is an award-winning filmmaker who shoots and edits. He has also done live event production, including mixing audio for Quincy Jones.