01/04/2012 19:07 BST | Updated 01/06/2012 06:12 BST

My Portrait of Damien Hirst: A Nipple is More Than a Dot

To me, Damien Hirst seemed like a typical bloke in the pub who enjoys a pint and loves talking about football and girls. When I was in his office, he was very excited about the castle he had just bought.

One thing I really like about my job is the unexpected surprises. I was called up by the Norwegian magazine D2, a regular client of mine, who explained that there was the possibility that I might get to take a portrait of Damien Hirst, although they were not sure if it would happen, as they had no proper appointment.

They had sent two of their best journalists who were working on the piece over from Norway to London and told me join them when they visited Hirst's office in Welbeck Street, central London, in case he said "yes" to a photo. He not only agreed and but he then also invited us to visit his factories were all the art was made.

To me, Damien Hirst seemed like a typical bloke in the pub who enjoys a pint and loves talking about football and girls. When I was in his office, he was very excited about the castle he had just bought. He was even more excited over the new identical watches he and his accountant Frank Duphny were wearing and he thought it was very boring to sit in front of the camera if as nothing was happening. That is why he wanted to touch his nipple. Sometimes I like to make people wait before I take photo. It creates a particular mood. It's a bit like when detectives interrogate suspects and the guilty talk more than they want to because they can't deal with the silence.

As I mentioned, Damien and Frank were very proud of their new watches. From what I understood, it was Frank who had made Damien rich and had persuaded him to stop taking drugs back in the '90s. He told Hirst to get sober and start collecting receipts for the taxman. Frank also had a vision of how amazing the complete puzzle of Hirst's work would look like if all the thousands of disparate pieces were put together.

But first, they had to buy all of those pieces back from Charles Saatchi. Daphny dragged Hirst out of a nightclub, told him how much money he could make and became a kind of father figure to him. It was obvious to me that Damien really loves Frank and they have a lot of fun together. One of my favourite photos from that day is of the two of them posing with their watches. Damien's assistant wrote to me after the magazine came out asking if they could have three copies of the photo - one for Frank, one for Damien and one for the archive. I imagine my photo hanging on the wall in Damien's office next to a Richard Prince print. When the request came a friend of mine said I should send it to them for free. I thought, "Fuck it! Why should the highest paid living artist in the world get something for free from me, who struggles to make ends meet?" So I invoiced them for it. I should have asked for a swap!

I think if Damien Hirst had been Lars Ulrich of Metallica, he probably would have sued the guy who sold him a fake Damien Hirst print on Ebay. Instead, he thought it was funny and displays it proudly in his office next to a photograph by his friend David Bailey. The irony is that if he signs it, it will, of course, be worth thousands.

Roughly 150 people were working for Hirst when I visited, spread across a huge hangar and some large warehouse spaces in the West of England. Arriving at the complex, I was surprised that they let us walk around freely looking at everything. One spectacle was three massive cows' carcasses crucified like Jesus and the two thieves. They were just lying there on the floor like stock in any warehouse waiting to be wrapped and shipped. I saw hundreds of fish, birds and other animals in glass boxes on poorly lit shelves.

My highlight was wearing a gas mask while entering the room where the dead animals were treated and then put in formaldehyde. Returning home, I felt lucky to have witnessed and photographed this bizarre world. Not many average blokes in the pub can tell their mates over a pint that they had bought a castle, signed off 100s of paintings worth millions and put a sheep in formaldehyde that day.