We were in the Odeon Covent Garden, a place where you can watch films while munching on sweets. The excited voice on the cinema’s telephone booking service had described the offering as a “romantic action drama”, but that fooled nobody.

Filmed with six cameras on to high-definition video, Glyndebourne’s penetrating summer production of Wagner’s epic of pain and ecstasy drew opera habitués eager to sample for £7.50 something that could otherwise have cost an arm and a leg. If there were opera virgins in this London audience, they were invisible.

Sightlines were perfect, though the film director Thomas Grimm’s close-ups, seen in a cinema, sometimes offered sights that Wagner wouldn’t have thought necessary. Isolde’s sweat, Tristan’s tongue. There were other distinctions to get used to. No stage presence; no live interaction; orchestral sound that leant toward the inferior – this Covent Garden projection turned a tin ear towards the London Philharmonic and their conductor Jiri Belohlávek. Note, too, the faint high definition lines across the screen, giving the skin in facial close-ups the texture of a sieve.

Yet, as minutes became hours in the Wagnerian way, you did adjust. And no technological peculiarities could knock out the production’s two substantial pleasures. One was Nina Stemme’s exemplary Isolde. From top to bottom, her voice knows no fear. More than that, the six cameras love her. Like René Pape’s noble King Marke and Bo Skovhus’s desperately loyal Kurwenal, she acted with every muscle, every stare and blink of the eyes. Not the case, unfortunately, with Robert Gambill’s vocally wayward Tristan – he was the film’s nagging tooth, although he improved with Act III’s delirium.

The other chief glory was the production itself. If any Tristan staging is going to be surgically dissected by cameras, let it be Nikolaus Lehnhoff’s. Given the importance of Robin Carter’s changing lights – playing across the stark vortex design by Roland Aeschlimann, half womb, half giant plughole – the production was already halfway cinematic. And with no clutter to distract, Andrea Schmidt-Futterer’s costumes leapt into new expressivity. It might at times be disrupting when cameras and editing slice up our gaze, but one reward was the ice-blue glint of chainmail and fur.

So, an imperfect night at the opera, but worthwhile. Glyndebourne next comes to the movies on November 29, when Handel’s Giulio Cesare plays at ten Odeon cinemas across Britain. Stock up on the sweets now.

Odeon filmline: 0871 2244007

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