Nothing raises hackles in the British film world more than the suggestion that some regional accents are difficult for the untrained ear.
The issue is that the comprehensibility - or not - of an accent might limit a film's market. Yet being subtitled or dubbed can also cause offence. The BBC's decision to air Ken Loach's Sweet Sixteen with subtitles triggered an avalanche of complaints.
"I think, frankly, there's a lot of laziness about accents," says Andrea Calderwood, a former head of drama at BBC Scotland and the producer of "accented" films such as Once Upon a Time in the Midlands. "We hear New York accents in films and accept that some words will slide past, but we'll get the gist. With British regional accents a kind of panic sets in: if people think they can't understand a few words in the first 10 minutes they switch off, but it's perfectly understandable if they get into the rhythm of the language."
When Sweet Sixteen was shown in cinemas in England, the first reel was subtitled to ease viewers into the heavy local Scottish. "It's not a question of being obtuse, it's a question of making the film accurate and then enabling people to go through it," said Loach. As far back as Kes in 1969, "the Americans said they understood Hungarian better than South Yorkshire".
Colin Vaines, head of Miramax in the UK, says: "This issue comes up if you're distributing films in North America. It's about getting the audience to feel comfortable at the start. If that means the actor has to loop a few lines to make it a bit more comprehensible, that doesn't seem to me to be messing with artistic integrity."
When previews revealed that US audiences were having trouble understanding the Edinburgh accents in Dear Frankie, the director Shona Auerbach re-recorded some lines of early voiceover. A few lines of dialogue in Trainspotting were re-recorded, too.
Contrary to belief, distributors are not eager to sacrifice authenticity. "If you've bought a film and you think it works, you want to leave it alone as much as possible," Vaines says. This applies especially to films by auteurs such as Loach and Lynne Ramsay, whose work is driven more by cinematic lyricism and emotional veracity. It's different with more commercial projects; a film version of Auf Wiedersehen Pet sank when financiers decided that the Geordie accent didn't travel.
But the New York Times critic Janet Maslin was moved to offer "heartfelt thanks to My Name is Joe for breaking the burr-and-brogue barrier with subtitles, so that the overlapping dialogue of its Scottish characters is entirely accessible. I've seen it untitled at Cannes and now in this negligibly altered version, and I can attest that the titles don't undermine the film. Struggling with dialogue is much more distracting."
Scottish accents aren't the only ones that create controversy. During the filming of Once Upon a Time in the Midlands "there was an issue from FilmFour that Robert Carlyle would keep his accent accessible," Calderwood recalls.
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The Ulster accent can also be problematic. When Bloody Sunday was screened for its distributors, "people did go, 'I can't understand a word they're saying,'" said the producer, Mark Redhead. "But the fact that the British were speaking one version of English and the kids from Derry were speaking another was central to the point about lack of communication."
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