Despite growing evidence that digital cinema can offer greater choice that the public wants, rollout in Europe in particular remains mired in an impasse over payment and business models.

That was the message of this year's Screen International annual digital cinema conference in London.

In his keynote speech, Bud Mayo, CEO of d-cinema pioneer Access IT, spelled out what he believes is the irrefutable argument for new technology - that it will boost off-peak admissions by offering more choice.

'Nobody is in a theatre for the most part Monday to Thursdays,' he said.

'We believe that digital cinema, in addition to better sound and image quality can enable those empty seats to be filled by providing many more choices and scheduling possibilities.'

Slow periods can be filled by alternative screening options for customers, he suggested.

'Music concerts, sporting events ethnic and religious evcnts and lecture series; these choices, live and pre-recorded, will expand dramatically over the next few years.'

'In fact any form of entertainment you find in an arena anywhere in the world will find its way into your screens at off peak hours that are attractive.'

He believes a relatively small amount of supplementary activity to the core film business could bring big results: A 1% increase in admissions in Western Europe alone would mean $600m, he said.

The argument was backed up by other speakers, who offered case studies of experiment in non-film content.

Mark de Quervain, sales and marketing director at UK cinema chain Vue. has experimented with live concerts and is planning a comedy show.

'We are in a learning process, finding out what works and what does not.'

The early efforts, such as a concert this year by veteran rock group Genesis, pulled in customers but de Quervain conceded that it was a huge effort to produce and it was not clear how future global releases would work out.

He estimated that live events and other non-film activity would account for between 1-3% of business.

The potential for charging a premium rate for such content remains one of the more attractive promises of d-cinema, and again there are now proven cases of customers willing to pay a premium rate.

Marc John, head of digital development at the UK's Picturehouse chain said an opera season from the Met in New York had packed out theatres - both at an initial $25 (£12.50) and the subsequent $50 (£25).

'People did not bat an eyelid at higher prices and cinemas said they not only attracted usual cinemagoers but new people.'

That public demand extends to a wider choice of film rather than simply replacement of feature content.

Peter Buckingham, head of distribution and exhibition at the UK Film Council said the recent experiment during the Summer Of British Film season had been hugely successful.

The council helped put a series of restored classic films - including The Dam Busters, Goldfinger and Brief Encounter in a wide range of cinemas across the country and found audiences highly responsive.

'It proved that people want a wide choice of films on the big screen, even if those films are available on DVD.

Most speakers estimated that alternative content to the current diet would amount to between one and three per cent of their activity.

But such changes inevitably ask questions of the business model.

Despite evidence of benefits digital cinema remains mired in aguments over who pays for installation that is already threatening some parts of the industry.

Nicolette Homes, commercial director at Carlton Screen advertising, which boasts a commanding market share in the UK, warned: 'unless we go digital in the next two to three years, I am not convinced we will still be in business.

'To run half the estate digital and half in 35mm is not possible in any way. We will just go bankrupt,'

Major business, she warned, wanted digital advertising but no one would tolerate the costs of a half-digital, half-35mm solution.

What Homes' point illustrates is that the wider industry knows it cannot stay where it is now, cannot support a halfway house and does not know if it is possible to find an equitable solution to please all parties in the future.

The conference heard that Germany is finding it hard to find a way to reach agreement on a rollout plan that will achieve growth without losing smaller cinemas.

Analyst David Hancock, of Screen Digest, said he feared the debate had led to a damaging 'politicisation' of the d-cinema issues in which tensions between demands for fairness and the free market had become a real issue.

The most promising breakthrough in Europe seemed to have come earlier this year when Arts Alliance Media (AAM), which announced a deal with Universal Pictures International and Twentieth Century Fox on the most developed model for sharing costs between distributors and exhibitors - the virtual print fee.

Further deals will come, AAM CEO Howard Kiedaisch promised, saying it was more a question of timing than underlying problems.

Julian Levin, evp digital exhibition, Fox Entertainment, said he understood the issues around VPF but warned there was a limit to the patience of studios for arguments that had led to what he called 'organised chaos.'

The current deals on the table needed to be taken up by exhibitors, he suggested, or they could end up paying all the bill for digital benefits.