Ian Burrell: The expansion of Sky Arts confirms that it isn't just a cultural fig leaf

Viewpoint: But Sky Arts has gained the confidence of institutions which would rather have been working with the BBC

Ronnie Wood is as handy with a brush as he is with a plectrum and his paintings can sell for £1m. But do his abilities as a guitarist alone qualify him to be regarded as a figurehead of the arts? In an era where anyone with a public profile is quickly deemed to be a "celebrity", broadcasters must tread carefully to avoid being criticised for ditching high culture in favour of ratings-friendly shows about the rich and famous. And that's especially true of a broadcaster that is trying to win a reputation as the new champion of the arts.

Which is why Sky Arts has chosen a two-pronged approach to its coverage and exploited the fact that it has two channels to fill with cultural content. On Sky Arts 2 you might find Placido Domingo in Handel's Tamerlano, or Sir Simon Rattle conducting the Berlin Philharmonic. But the lead channel, Sky Arts 1, is largely characterised by "what is pejoratively called 'Dad Rock'", says Sky Arts director James Hunt.

So when Sky Arts gets transformed this week with a trebling of its budget and a new position high up the programme guide (it's available on Sky, Virgin Media and Tiscali, but not on Freeview), the Rolling Stone will be at the heart of the offering, interviewing his chums. Sky Arts has also positioned itself as the home of the music festival, taking advantage of a summer when the BBC is shorn of Glastonbury, which is taking a year out. Last week Sky executives were in meetings planning up to six hours coverage a day of the Isle of Wight festival, all in 3D. The channel has assembled a portfolio of 13 festivals (including Download, Lovebox and Hard Rock Calling), which means it will have a live broadcast event almost every weekend throughout the summer.

When BSkyB bought the high-end Artsworld channel in 2007, many observers saw it as a classic and cynical Murdoch strategy for countering the carping of the chattering classes and attracting a new class of subscriber which had not been engaged by the previous offering based on football and Hollywood movies.

But Sky Arts has won a reputation for innovation in arts television and gained the confidence of institutions which, frankly, would rather have been working with the BBC. It offered the first live televised preview of an arts exhibition (Leonardo da Vinci at the National Gallery), and simulcast it to 41 cinemas across the country to promote the brand. It screened the first original live theatre in Britain for 35 years, an idea suggested by Sandi Toksvig.

As well as music festivals, Sky Arts covers four literary ones. It broadcasts for 30 hours from Hay-on-Wye, rather than the minimalist coverage of its previous broadcast partner Channel 4. Melvyn Bragg and his Director's Cut production company were persuaded to give Sky Arts The South Bank Show, which Hunt describes as "the world's leading television arts brand", and which had been axed by ITV after a run lasting more than 30 years.

As part of a raft of new shows being launched on Sky Arts this year, the channel will show a four-part documentary on the photographer Richard Young, made by the film-maker and musician Don Letts. It will examine iconic shots taken by Young of subjects including Kate Moss, Vivienne Westwood and Tracey Emin.

Once again, the channel is stepping into the grey area where the arts and celebrity collide. But Hunt sees his channel as responding to a growing public hunger for intelligent material, reflected in the growth of literary festivals, book clubs and debating events. "It couldn't be clearer that this is not a fig leaf channel, we are taking it dead seriously."

i.burrell@independent.co.uk