December 4, 2018

Recording a Multi-day Event

I was asked to suggest equipment for recording a 5-day seminar.  It is estimated that about 30 hours of recording will be done in total.  This will be a pretty standard corporate knowledge sharing event - few speakers talking to a small audience while using their laptops to share slides.  I suspect there will be live coding examples, so the resolution of this part will have to be reasonably high.  Working on a whiteboard will be an option, so the camera will have to be manned.

Audio

I rely on Sennheiser G3 for recording the speaker.  Batteries (2xAA) can be swapped during the breaks for continuous recording.
For ambient audio and as a fall-back I use Sony PCM-M10 recorder. Batteries (2xAA) can be swapped during the breaks for continuous recording.  The recorder has space for more than 10 hours of recording, so the daily backup is desired.  I record in PCM16/48kHz.  The built-in 4GB flash is sufficient for 5h 45min of recording so daily backup is required.


Desktop/Slides Recording

My tried and true solution is a hardware recorder with HDMI pass-through.  External power brick is used, so no batteries to worry about.


AverMedia C285 is probably obsolete by now but it certainly does the job - it supports resolution up to 1920x1080 at 30fps.

The recorded stream is stored on the internal 2.5" SATA drive - I have a set of three such 128GB SSDs.  Each can store more than 13 hours of 1080p 30fps video/audio stream in MP4 container.

Speaker/Audience Recording

Use GH5 with 12-35 2.8 zoom lens to record speaker and audience.  4K recording recommended so that a no loss zoom-in on the speaker face can be done in post.  A single battery will comfortably power the camera for about 2 hours.  I have 4 batteries, so daily recharge of those will be required.  Camera has 2 SD card slots. Usually I record 4K 30fps in MOV container at 100 Mbps rate. Two 128GB cards should suffice for 6 hours or live video recording.  Daily backup will be required though.

Post Processing

During post processing the following tasks are performed:
  • clips are synchronized;
  • dynamic compression for audio is performed;
  • video exposure/color adjusted ;
  • content is edited to maintain tempo into clips of reasonable length - less than 45min;
  • content is rendered to desired resolution (720p?  1080p?) and bitrate - YouTube guidelines recommended;
  • Opening/closing credits are added.  Adding corporate branding is an option as well.

Storage Requirements Summary

For a week-long events the following storage is required:

Recorder   Built-in StorageStorage for a week-long (30hours) event
Audio4GB, 5 hours20GB
Screen120GB, 13 hours300GB
Video2x128GB flash, 6 hours   256GB*5 - about 1.4TB

Seems to be totally manageable.  If full time video can be avoided, those become totally trivial.