[Stooky Bill]

Hello ☺ 


What you're seeing on Zoom/Teams is a automatically-generated composite of everyone on the call, or a single person talking, as captured by their webcam.

At the BBC the machines that run these calls are not located in the gallery, they are centrally controlled either by a media hub (World Service way of working) or MCR themselves (News workflow). The receiving audio and video is then patched into the internal routing switcher known as BNCS for any gallery to pick up and route to one of their Outside Source lines. The gallery also has the ability to request "2 way clean feed", which only one gallery can have at any time, and which basically pushes a mix minus from that gallery's sound desk, generated from the OS line it is on's fader, back through the BNCS network and then into that same computer in the Media Hub or MCR.

There is no technical reason why you couldn't send video down that as well, but traditionally all clean feed lines were audio only. When using more traditional technology such as satellite lines, MCR have to dial up the mobile phone of the correspondent and send clean feed down the phone line, as there are obviously no 2-way satellite lines.

The problem is you'd then need the gallery's vision mixer to send something - and what do you send? An isolated camera which may move, refocus or be stood in front of during the interview? What happens when the presenter needs to move to the next segment in a different place of the studio where the next guests waiting? Maybe you could do a locked off "ceiling cam" showing the whole studio, but this would be really poor quality.

A couple of quick points on this. Firstly by '2 way clean feed' I assume you mean it's the clean feed for the two-way, not a clean feed in two directions which isn't a thing. 

Secondly satellite feeds are one way, but that's not to say you can't have two, one in each direction. So the guest is being uplinked to the BBC and a reverse vision uplinked by the BBC back to the studio where the guest is. Doesn't happen often and rarely in news unless the presenter is on an OB. Though it's more common to use a low latency IP based reverse, this is always the case for autocue feeds for obvious reasons. 

A lot of satellite lives for news are two-way via satellite as the clean feed is sent back over satellite to the uplink truck 

Reverse vision via Zoom or other services like Skype, Facetime and WhatsApp is used sometimes. Sometimes the contributor had to see what's happening in the studio. One example is the kids show Saturday Mash Up, the contestants playing a game at home get a reverse vision from a seperate output of the studio to play their games