When Ann Widdecombe demanded that my film about new art in China, Beijing Swings, be taken off the air in 2003, I suspected I was doing something right. When the Chinese subsequently banned me from going back there and the Third Secretary at the Chinese embassy popped up in the media to describe the film as “very damaging” to the image of China, that suspicion hardened into a certainty. Any film that can inspire critical concord between Ann Widdecombe and the Chinese authorities is surely treading on interesting toes.

Beijing Swings rounded up the hard-core rebel artists of China and listened to their complaints. Not the tame auction-monkeys who are currently raking in millions at Sotheby’s and Christie’s with their trite political iPop, but the determined naysayers who refused to be house-trained and were protesting as loudly as they could about the destruction that was being visited upon Beijing by the upcoming Olympics — the families that were being shredded, the communities that were being bulldozed, the undesirables who were being “lost”. Their message was: if you think our art is shocking, you should see what our authorities are doing to our country. Chief among these naysayers was Ai Weiwei, the original artistic consultant to Beijing’s Bird’s Nest Olympic stadium, who has a new show in London.

Ai Weiwei had a genius for annoying his government. We used one of his photographs of a young Chinese girl lifting her skirt and flashing her knickers at Chairman Mao as the publicity still for the film. And long after we’d gone, when the cantons were reduced to rubble and that grotesque heavy-metal Bird’s Nest had risen out of the ashes of so many destroyed lives, it was Ai Weiwei who continued to protest on a daily basis about what was happening. If ever an artist had a stubborn streak, it was Ai Weiwei.

So it’s sobering to see how thoughtful and quiet he seems to have grown in his new show at Albion. Anger, you feel, has turned to sadness. A battle has been lost. And we in the West contributed plenty to the defeat. Two huge works dominate this display. One is a line of extra-large colour photographs detailing a day in the life of the half-built Bird’s Nest stadium — 24 melancholy photographs for 24 melancholy hours. The other is a claustrophobic installation of tottering bamboo sticks that fills two of Albion’s larger galleries.

Bamboo is the magical ingredient that has made modern China possible. Those who have been to Beijing will know already that the Chinese construction industry relies utterly on hand-tied bamboo scaffolding. Every thrusting steel-and-glass phallus that today brutally rends the Beijing air began life as a spindly chopstick heap of interconnecting bamboo struts. Thus the 21st-century futurism of which China is so destructively proud was achieved with the aid of man-eating building methods perfected in the bamboo age.

This poignant paradox lies at the heart of Weiwei’s lament. His art constantly pits the human against the machine; old values against new ones; bamboo against steel; the poetic truths of then against the poetry-less lies of now. In this show, the tottering scaffolds of floor-to-ceiling bamboo play curious and sophisticated games with the blank white cube in which they find themselves. Bamboo’s strength is, of course, belied by its size. Just as there seems to be something miraculous about the manner in which the grotesquely large metal knots of the Bird’s Nest were initially kept in place by delicate trellises of bamboo, so the thin scaffolding towers of this installation fill their predictable space with unpredictable tensions and thrusts. It’s like watching a thin, wiry bloke fighting a huge lard-arse. The thin bloke is the one you cheer.

There’s more. Among the bamboo struts, a strange assortment of chairs and stools appears to have sprouted like fungi from the wood itself. It’s a thoroughly puzzling sight. To me, the sprouting chairs seem to be saying something about the unstoppable presence of the human being on the scaffold: each chair might represent a missing worker who has given of himself for the project. I am being fanciful, I know, but Weiwei’s art allows you to be fanciful. And the rickety bamboo scaffold definitely feels like a low-tech encapsulation of the high-tech absurdities of modern China.

The big sequence of photographs of the Bird’s Nest being built was taken at hourly intervals on a single day in 2006. It’s a day in the life of a monster. At night, the sudden showers of welder’s sparks and the bright flashes of floodlights briefly lend the half-built stadium the excitement of a fireworks display. But as the dawn rises and the monstrous metal skeleton looms slowly out of the mists, you notice how dead it looks. Later in the day, when the sun finally breaks through the smog, the glowing green of the surrounding AstroTurf briefly jollies up this horror, like a smudge of lipstick on the face of a corpse.

What is marvellous here is once again the pitting of old poetics against modern realities. Chinese art has spent 3,000 years enjoying beautiful natural sequences — the changing seasons, the hours of the day, the mountain observed in all weathers — and even the crude, metal knots of the Bird’s Nest have a best side to show you if the light is right. Thus, at the far end of this endless day of photography, the sky turns rosy, and I’m damned if this mouthful of metal teeth doesn’t begin to resemble a kingly crown silhouetted against a sunset.

Also at Albion, the joyously moonstruck Katie Paterson continues her wacky love affair with the night. Last year, you may remember, Paterson transcribed Beethoven’s Moonlight Sonata into Morse code, which she bounced off the moon and back. However, not all the music returned. And the resulting fragmentary sonata was played in the gallery on a tearful pianola.

This time, Paterson has persuaded the scientists at a famous light-bulb company to create a special bulb that replicates moonlight as accurately as possible. While this ghostly moonbulb fills the darkened gallery with atmospheric pools of lunar light, a nearby storage rack, neatly stacked with 289 of the bulbs, each of which lasts for 2,000 hours, represents all of the moonlight that falls on us in an average life of 66 years. How frighteningly tiny is this lifetime of moonlight.

Ai Weiwei and Katie Paterson, Albion, Hester Road, SW11, until November 14.

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