Originally Posted by POTD:
“Why would you need to refilm the audience reaction anyway?
Generally you refilm sections if the audio wasn't good enough, so on programmes like HIGNFY they might ask the host to repeat a couple of lines.”
Because in a studio you have a controlled environment built for purpose. You can set up your camera angles very easily free of any obstruction to film the action both on and off the floor.
The Tower Ballroom wasn't built for TV so it is likely that filming in there presents a number of operation challenges. For example a panning shot to move from the floor to the stalls may have to cross the path of a pillar.
So in such cirumstances it would be quite reasonable to set the cameras up to take some footage say from the dance floor., then move it to film some back ground, textural footage. The alternative would be to have twice as many camearas and camera operators which is expensive.