By Alex Webb BBC News Online entertainment staff

The Royal Opera House in London's Covent Garden has long been sensitive about the complaint that it caters only for the rich.

Well before the recent refurbishment - which was only financed after more promises to widen access to the opera - the company started presenting occasional operas for free in the 19th Century piazza behind the theatre.

And what better way to prove opera's democratic credentials than the story of four penniless students in Paris - set in the era the piazza was being built?

Puccini's La Boh�me was the first opera to be screened this way, back in 1987, with Placido Domingo as leading man Rodolfo.

Vargas is a tenor with real stage skills

In 2002, Domingo's shoes were to be filled by a fellow Mexican, Ramon Vargas, on a typically grey evening in London, pregnant with the threat of rain.

But the opera-goers filling the piazza on Thursday evening were cheerful enough.

Young and old, ethnically diverse, they also ranged from dilettante opera-fanciers to hardened opera buffs.

Appropriately enough for La Boh�me, for many the motivation was financial.

Artform

James, 25, had come from Richmond: "I think it's good they do it, but I think they should do it more often.

"Opera's such a great art form that it's a shame it's so expensive - even a balcony seat costs �40 and that's too much for most people."

Seats were provided for the less nimble

Patricia, an accountant who had walked up from her Fleet Street workplace said: "I think it's brilliant because it's quite expensive to see an opera."

And Christopher, 58, said: "I go to the theatre itself for quality performances, but when I don't feel like paying �66 I come and listen out here. The sound's very good, too."

The open-air setting couldn't provide quite the sense of anticipation that curtain up gives in a theatre - there was too much passing traffic, for one thing - but the charm of the opera's famous opening scenes was powerful enough.

The filming - which gave us close-ups and different angles - actually made some of the scenes more effective.

Hopeless love

The famous arias by which Rodolfo and Mimi find each other - Che Gelida Manina and Mi Chiamano Mimi - were all the more touching for the principals' genuine attempt to create a naturalistic emotional atmosphere, not something all operatic stars can be accused of.

It was interesting to watch the music work on the crowd, some of whom chatted and some of whom were transfixed by the hopeless love of Rodolfo and Mimi.

WPC Mandy King, one of just a scattering of police on duty, said the crowd were "extremely well behaved."

Better behaved than the riotous students in Boh�me, that was for sure.

Pat, one of the opera-goers who had grabbed a seat near the front, could remember the first of these screenings, back in 1987.

"I remember standing in the back streets just trying to see. I remember Domingo but I was a long way away," she said.

Pat was in no doubt that free opera is a good thing: "I'd like to think that someone passing might like it too - I just don't think children are educated in classical music they way they used to be."

And in Covent Garden's piazza on Thursday night it did seem that the idea of opera for the people was not, perhaps, just an idle fancy.