I haven’t seen a map for a week. I am not entirely sure where I am, but it is Jianchuan, another picturesque village in another mountain valley, green hills topped by wind turbines in the distance. This is another Bai area (they are the dominant minority in this region), where the Dong family make old-style black pottery. They dig clay from the mountainside and leave it to bake in their courtyard for a year, before breaking it up with a hammer, sieving it and wetting it, to make their sludge. Then they fashion it into pots, and throw in charcoal that bakes in a black or silvery-grey finish. Their specialities include wamao – a fearsome tribal totem cat with an open-mouthed roar that makes it look like a triffid, used as a roof guardian. And pots and cups and the usual ceramics.

The potter is in his fifties and only speaks halting Mandarin. His son trained as a woodcutter, but then went back into the family business because he feared his Dad was lonely. Since it is too familiar to address them by their given names, and “Master Dong” doesn’t make it clear which one I am talking to, I resort to addressing them as Big Dong and Little Dong.

Big Dong has been chatty and affable all the way through the morning. He has been trying to push pungent Yunnan cigarettes on the crew, and boiled tea in the Yunnan manner, heating the pot rather than the water, until the water fizzes on contact with the ceramics. But the moment the camera is on him, and the light is on his face, and he is being urged to look at me and not the director, and the sound guy is rolling and the clapper loader is snapping a board, he clams up in stage fright. He swallows, he stammers, he offers one-word answers and looks nervously around him. It’s almost impossible to get a clean sentence out of him, and he knows this isn’t how it is supposed to be, so he starts to sweat. This means more dabbing, more light changes, and more faffery, and it just becomes a vicious circle of bad takes.

People feel the camera lens staring at them; they feel the weight of the attention of the crew suddenly focussed on them; they feel the importance of this moment, above all the other moments they have lived that day, and a relay blows somewhere in their brain. Some interviewees turn into emotionless robots, declaiming facts at the camera, purged of all personality and humour. Others become hyper-conscious of every word they utter, double- and triple-thinking every sentence until they clam up. Some, like Big Dong, suffer from a different kind of panic – the sudden realisation that they are talking not to my smiling, nodding, solicitous face, but to millions of people in thirty different countries. At times like this, we have to cheat their brains back into forgetting that fact.

The director puts Little Dong on camera instead, with Big Dong nodding assent at his side. Little Dong is at ease and chatty, knowledgeable about his people’s heritage and the history of pottery. He laughs and jokes, and delivers a far better set of responses, sufficient for Big Dong to come back on camera and ape some of his son’s answers.

We sit and drink bitter Yunnan tea from little thimble-cups as the crew faff around. The director of photography sneaks some shots of Big Dong laughing and joking in an attempt to find footage to cut in that doesn’t look like he is being interrogated by the Gestapo. Little Dong reveals that he is a graduate of a Xi’an polytechnic – where he learned wood-carving – and I start to suspect that the fluency of his answers reflect academic study rather than traditional artisanal knowledge. Whatever, the director just wants to get something in the can.

The trick has worked. Both Dongs are now happily chatting away to me. I sneak a sideways glance at the camera, and see the Record light is back on, but Big Dong has been ushered back to normal by the simple expedient of not being reminded that this is his big moment.

Jonathan Clements is the author of The Emperor’s Feast: A History of Chinese Food in Twelve Meals. These events featured in Route Awakening S02E06 (2016).