Marco Bechis' fourth feature Birdwatchers, was one of the most talked about films at this month's Venice film festival. The powerful drama about the effects of globalisation and colonisation on the indigenous Guarani-Kaiowa people of Mato Grosso do Sul, a southern, forested region of Brazil provoked much conversation for the way the film reverses traditional casting: the natives star, with the seasoned European actors taking the supporting roles.

But this was not without its problems, reveals the Italian-Chilean director, who had to explain to his lead actors what a camera was.

'They are not isolated from TV but they have never been in a cinema,' Bechis explains. 'Ambrosio Vilhalva (who plays the troubled tribal leader) had been in a cinema once but was afraid and tried to escape.'

Bechis met Vilhalva through Nereu Schneider, a human rights lawyer working to defend the community's rights. Bechis was keen to put their story on film. 'They had a great oral tradition and I felt they were potential actors.'

However, Bechis didn't want to make a documentary. 'We wanted 'an exchange',' Bechis explains. Making it as a feature and employing members of the tribe as actors (in roles loosely based on themselves) allowed them to have contracts and receive hourly wages, transportation and meals.

'We started by explaining to them what cinema is, and showed them films and explained how the machines worked,' Bechis recalls. 'I tried to slow down the 'cinema machine'.'

Bechis screened the actors Alfred Hitchcock's The Birds and Sergio Leone's Once Upon A Time In The West to teach them 'how to deal with silence and the power of the close-up'.

Birdwatchers is the third collaboration between Bechis' Karta Film and Amedeo Pagani of Italy's Classic Films. Brazil's Gullane came on board as the local partner and backing came from Rai Cinema. Celluloid Dreams is handling international sales. Bechis was previously at Venice in 2001 with Sons And Daughters, a drama about the children illegally adopted during Argentina's military dictatorship.

'I need permission from myself to make a film,' says the Italian-born Bechis, who spent much of his childhood in Latin America and is now based in Milan. 'Generally this is something reality gives to me, (a story that) needs to be told. My work is trying to find a way to tell this story.'

For his next project, Bechis says he would like to make a political film about Italy. 'It's too soon to tell, but it will probably be about what is happening with Italian people.'