‘It was -10 in the air, but nearly 40 degrees in the water’: Magali Chesnel’s best phone picture

The French photographer on the joys - and difficulties - of taking pictures in Iceland's Blue Lagoon

It wasn't until Magali Chesnel was on her flight back to Geneva that she figured out why the people she'd seen swimming earlier that day had been wearing bin bags on their heads. After a week of solo travel around the south of Iceland, the French photographer had spent the morning at the famous Blue Lagoon geothermal spa, just a short drive from the airport. Returning home, she realised her hair had turned coarse and brittle from the silica in the pools. If you ever visit, use hair conditioner! Or a garbage bag!" she warns.

While she expected the shots she took of the bag-wearing bathers to be her favourites, it was actually this one that came out best. The six Icelandic teenage boys were laughing, chatting and drinking ice-cold slushies in 38C water in a scene that later reminded her of Leonardo da Vinci's The Last Supper. I studied art when I was younger. I like my photos to have an element of confusion; are they a photograph or a painting?" Chesnel says.