As British troops prepare to leave Afghanistan, their experiences there are being reflected in a series of striking photographs posted on billboards across the UK.

Robert Wilson, a successful commercial photographer, first went to Afghanistan by chance. He had never been to a war zone before. His journey from the advertising studios of Europe to the deserts of Helmand province began seven years ago when an enthusiastic amateur photographer, Euan Goodman, came to see him for some advice.

Image copyright Robert Wilson

While looking through Goodman's portfolio of routine British scenes, Wilson chanced on a print at the back. "It was incredible, it looked as if it came from a film set. There were people running and there was a big explosion in the background," he says. He asked Goodman where it came from and was told "That's my day job, I am a soldier."

Wilson spent hours looking through the images on Goodman's laptop and struck up a friendship with him. When Goodman's commander, Brig Andrew Mackay, was looking for a way to record his unit's next deployment to Afghanistan, he commissioned Wilson to come and take photographs. The result was a best-selling book.

Image copyright Robert Wilson

This year Robert Wilson has been back to Helmand to mark the end of Britain's long conflict. His pictures are going up on huge billboards across Britain this week, some close to military bases, others not. For the images, Wilson was looking for ordinary human details to personalise the war, and has chosen sites across the UK where he can juxtapose his photographs with scenes of normal life.

For example a billboard showing a makeshift military bus stop in Camp Bastion will go up on the side of a bus stop in Yeovil and a photograph of a makeshift garrison church will be displayed opposite a church in Camden, London.

Image copyright Robert Wilson

They have no written explanation, but will stand for themselves as images, with just a QR symbol for further information to be downloaded online.

Wilson wanted to photograph things that he recognised, otherwise the conflict would have felt remote. Normalising the experience enabled him to bring it home. "Then you think about it not just as the guys who live out here and that's all they do. It's guys with mums and dads, and brothers and sisters, and wives and kids," he says.

Image copyright Robert Wilson

In a canteen hall in Helmand, he found tables made from used rocket cases, and in Kabul, where there were rows of blast-proofed shipping containers being used as bedrooms, there were rugs on the ground outside. The homely details humanised the environment.

Image copyright Robert Wilson

Image copyright Robert Wilson

He was fascinated by the junk of war. Material that was not being brought home had first to be cut up so it could be sold as scrap without being turned into bomb-making equipment. He took startling images of twisted wire and canvas left after Hesco barriers had been emptied of the sand that had turned them into blast walls. He realised that "the camps were built out of nothing, from the earth that was there".

Image copyright Robert Wilson

Image copyright Robert Wilson

In Camp Bastion, Wilson climbed through the narrow trapdoor to the top of an observation tower, where the RAF regiment watched the Afghan desert.

Image copyright Robert Wilson

He felt it had an alien quality, full of stark contrasts between the military machinery and the unforgiving, relentless sunlight. The big open windows looked like paintings and left a lasting impression on him. "You have these beautiful landscapes - clear blue sky, fluffy white clouds, and the pale yellow floor of the desert," he says.

Image copyright Robert Wilson

He was accredited, not as a journalist, but as a war artist, and used the type of camera that he would normally use to shoot celebrities in a studio.

The photographs have gone through the same post-production process that he would use for a commercial shoot, adding contrast, sharpening the images, and desaturating the colours. For Wilson, the post-production editing enabled him to crush the tones and recreate exactly the harsh glare of the sun in the Helmand desert.

The cameras he used in Afghanistan had a very shallow depth of focus which meant he engaged closely with the eyes of the people he met. He went in with no agenda "other than to photograph what interested me, and a lot of the time it came back to portraits, because that's my main interest".

Image copyright Robert Wilson

Image copyright Robert Wilson

Some of the pictures he took on his 2008 trip are also going on show in an exhibition timed to coincide with the billboard project.

The most powerful portraits from that time were taken during a couple of days in the middle of the three-week period he spent in Afghanistan. Then, British troops were engaged in intense daily firefights with the Taliban. One day Wilson was waiting for a helicopter to move on and he saw a group of soldiers who had just come in from a three-week patrol.

"They were looking quite bedraggled. And while they were having a debrief, I noticed they had this thousand-yard stare. I was the last person they wanted to see at that time, but after the debrief, I took three or four frames of each guy and let them go."

Image copyright Robert Wilson

His pictures of dusty war-weary soldiers were a long way from the usual sanitised upbeat images preferred by the media minders at the Ministry of Defence. But the commanding officer of 52 Brigade, Andrew Mackay, was happy with them as they showed the reality of the conflict he was facing and how his troops were dealing with it.

The cover of the book showed the portrait of an individual soldier who had caught Wilson's eye. They were at "JTAC Hill", then the southernmost point of the British deployment in Helmand. Legend has it that the lookout post on the hill was built by Royal Engineers in an earlier Afghan campaign in 1841.

When Wilson went there in 2008, British troops had pushed the Taliban back just 300 metres in the previous year. It was early in the morning, and Wilson asked the soldier to go to the top of the hill to catch the dawn light. The look in his eye tells a graphic story that Wilson only fully understood when the man said "Can you make it quick? I have my head above the parapet."

Image copyright Robert Wilson

Image copyright Robert Wilson

Image copyright Robert Wilson

Photographs by Robert Wilson

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