Taping of Late Night with Conan O'Brien's final episode began with a surprising quiet and darkness falling over the audience as someone counted down the last five, four, three, et cetera, when Max Weinberg began drumming hard and the studio monitors played the opening credits --- a montage of opening credits they'd had over the years and used for just the final three shows, as it happens. The taping of a late night talk show like this is very close to what you actually see on television, except that things like opening credits or cutaways to whatever movie the guest is promoting are shown on monitors which the audience more or less watches and the performing people watch as well, or talk with producers, or get a drink of water while it doesn't appear on TV.
The major difference in being in the audience, besides being surrounded by it all, is that it is much louder. The band is loud to start with, and the studio speakers play as loud as they can without producing feedback or legally provable hearing damage, and the audience --- whatever the show --- will make as much noise as they possibly can. I could tell that near the end of the opening credits the announcer, Joel Godard, made some quip --- itself a callback to the earliest shows' openings, when he always had a joke --- but there was no way to tell what it was in studio. (At home I learned what it was: ``I hope Conan likes the farewell gift I got him ... big, beautiful flames!'')
At the end of the opening credits the audience jumped up in the first of what would be many, maybe honestly too many, standing ovations, of which I believe only two and a half were detectible on-camera. This was briefly visible, and the one at the close of the show was, and one for executive producer Jeff Ross was mentioned by Conan when he said to sit down, ``You're cheapening my standing O''. Well, the audience is always a cheerful, excited crowd with this energy feeding back on itself, and we're probably fairly lucky that it's used to a silly and amusing purpose.
Trivia: On the afternoon of 26 March 1859 Edmond Modeste Lescarbaut observed a disc moving across the Sun. This formed the start of the search for the intra-Mercurial planet of Vulcan, as this appeared to be a fortunately observed transit. Source: In Search of Planet Vulcan, Richard Baum, William Sheehan.
Currently Reading: Waking Giant: America in the Age of Jackson, David S Reynolds.