Video recording

Live video lecture recording environment

We set up some equipment for recording video lectures that students can watch online. This is a brief summary of the equipment that we are using and our process.

Room

Choose a quiet, well-furnished room with very little echo. If that is not possible, prefer a large, quiet room rather than a small, quiet room. (In all cases, “quiet” is very important.)

Presentation equipment

Video equipment

Audio equipment

Editing equipment

Process equipment

Process

With the monitor off, determine the best lighting conditions for the room that do not cause reflections in the screen. Turn the monitor on, check the presenter’s brightness relative to the screen. The ideal is to have the presenter's face as bright and as clearly visible as the monitor contents. Use any combination of natural light, room lights, and if necessary a “studio” key light (in front and to the left of the presenter) and fill light (far right, to light the presenter if they are looking at the monitor). Set the colour temperatures of the lights to match the colour temperature of the monitor. (Our lights and monitor are all set to 6500K, which is close to daylight temperature.)

Clip microphone to presenter, then into the transmitter; connect receiver to camera. Turn off automatic gain control in the camera. Ask presenter to speak very loudly and check that the levels on receiver and camera just reach into the yellow zones. Check audio sounds loud, distortion-free, and centred (equal volume in left and right ears) in the headphones.

Connect laptop to monitor, show first slide, focus camera on slide, turn off auto-focus. Select “fluourescent” white balance on camera. Adjust exposure if necessary and then turn off auto-exposure (or enable auto-exposure lock if using a DSLR).

Check camera position: presenter and slides should be visible, and fill the frame. Make sure presenter knows the limits of movement in both directions.

If there is a time limit, set the timer. Deploy “QUIET PLEASE” signs outside the room.

Count down with fingers from 3 to zero; turn on camera between 2 and 1, point to presenter at zero, make and record presentation. Start timer if required. If presenter makes a mistake: stop and restart recording from a point just before the mistake. When presenter indicates the end of the presentation, wait one second then turn off the camera.

Transfer recording to computer. Check audio and video quality.

Edit video. E.g., for Shotcut: Create new project in video editor. Load clip(s) into timeline. Trim excess silence from start and end of clips (leave about 1.5 seconds). Trim overlapping part from ends of clips with mistakes. On first clip: add “fade in audio”, “fade in video” filters. On last clip: add “fade out audio”, “fade out video” filters. If audio levels are not good, or fluctuate, select entire track and add “Normalise: one pass” filter (our usual settings: 10s averaging, 1dB/second max gain change rate, -20LUFS target level). If exposure is not good, select entire track and add “brightness” filter. If the colour is too strong or too weak, select entire track and add “saturation” filter. Export the video using default 1080p or 720p presets, which generate good quality and relatively small files.

At the end of the day, plug wireless transmitter, receiver, and camera battery into charging cables/devices.

Create a checklist of your particular process, print it out as large as possible, and fix it to a whiteboard next to the recording equipment. Until you have memorized your process, have someone read each item and tick it off on the whiteboard. Remember to include “clear ticks from whiteboard” as the last checklist item.