How does live telecasts work and how do they switch cameras while the audience are watching the show or the concert lively?


How does live telecasts work and how do they switch cameras while the audience are watching the show or the concert lively?

In: Technology

There’s the producer/director in some sort of master control room. This room has monitors that show the feed from all of the cameras and the director will tell the switcher operator when to switch to what camera. The director also has communication with the camera operators so he can tell them where to point & what to zoom in on. The director usually also has a script or timeline as to what is going to happen so he can prepare camera angles & positioning.

I run master control for a small network and do live telecasts on a regular basis.

So for a venue like a live concert, the station will run a mobile production unit. Essentially a small TV studio packed in the back of a box truck. Several EFP (electronic field production) cameras will be set up around the venue. You’ll usually have one wide and one for closeups for a basic shoot. Bigger productions will have more for different shots. Overhead, jib (camera on a boom arm), action cameras (like a goal cam for sports), etc. These will be connected back to the truck’s CCU (camera control unit) via long cables. The CCU lets operators inside the truck adjust camera colour and iris, or remotely control some cameras.

The CCUs are connected to a switcher. Which is exactly what it sounds like. It’s a big routing panel with all the cameras listed on it, as well as any graphics or pre-recorded video sources. The technical director will switch between cameras, as well as tell camera operators which shots they want and which camera they’re going live to next. You’ll hear them give directions like “ready one, take one”, to instruct Camera One’s operator to stand by, and that they’re now on the air.

Audio is pumped in from microphones through a separate sound mixing board. Usually through XLR cables. Sometimes through the cameras depending on the setup. It gets combined with the video inside the switcher.

The truck then sends the signal back to the station; either using satellites, microwave (those big masts you sometimes see on top of them), cellular (becoming more common), or fiber optic feeds (for frequently used venues). Back at the station, these get sent to master control.

Master control runs the station’s automation software. They have a big playlist with the live sources, pre-taped shows, and any commercial breaks. The live feed comes into the main router where it’s fed to the channel servers. Master control operators will then provide time queues for the truck and manually role any breaks. They also monitor the feeds for quality.

From there, it leaves the channel servers and gets sent either to a broadcast antenna, or to a cable/satellite company’s head end for distribution to subscribers.