Rosie Barnes was lying on the grass, looking up at the sky with her 18-month-old son when a 747 flew overhead. "Tiny plane," said Stanley, an early and often eloquent speaker. Though Rosie did not know it at the time, the comment - an accurate description of what the little boy could see - triggered a 15-year project.
Rosie, who is a photographer, needed an exhibition subject. Her husband had booked her a week's gallery space as a Christmas present, aware that the early stages of parenting had left her little opportunity for creativity. "I had to put something in it. The only thing on my mind was Stanley so I began wondering how a child eventually 'gets' concepts like scale, reality and emotion."
When the resulting exhibition, A Boy's Eye View, was finished, Rosie put the collection aside and pointed her professional lens elsewhere. Eighteen months later, Stanley was diagnosed with autism and she found herself once again turning to the camera as she tried to make sense of her son's unexpectedly different world.
"I looked back over those early pictures and was shocked that they suddenly all seemed to be about autism," she says. "It was very poignant. The themes are ones he still struggles with."
The toddler she began to photograph is now 17 and Rosie is publishing Understanding Stanley: Looking Through Autism. It is a collection of pictures - some of Stanley, some of the world around him - taken throughout his childhood, which have something to say about his life.
"As his mum and as a photographer I wanted to get under the skin of how it might be for him." The project was open-ended, and some years in, Rosie realised it would make a book. "A 'what it feels like', not a 'what you should do' book. It had to be a thing of beauty in its own right, something you would want to look at. Pictures can resonate and stay with you in a way words alone might not."
Understanding Stanley is the book in which Rosie might have found solace in 2000, when she sat alone, the room darkening around her, reading through a pile of leaflets she and her husband, Martin, had been given along with their son's diagnosis earlier that day.
"The words were so horrible. They were about children with autism being bullied, abused. It was all profoundly depressing. There was no subtlety or balance," she says. "I'm not convinced words are the best place to start."
For a little while, Rosie recalls, she took no pictures. Then, waiting to meet a friend in a park, she snatched a photograph of a swan, its graceful neck fully submerged and just visible through the water.
"Later I saw that like the fairytale of the Ugly Duckling. It seemed to be a metaphor, but it was also such a quiet and peaceful image. It is about Stanley, about autism, but it leaves you with room to breathe. I wanted to take pictures which invited people to think, but didn't tell them exactly what to think."
"Maybe people won't always know what they are seeing. It might not be what they are expecting, but if they start at the beginning and work through they should get a feeling of what life with autism might be like."
While many parents of children with disabilities are upset by staring strangers, Rosie meets their curiosity with mixed emotions. "I want people to see. We need to look - within reason, of course - in order to understand and accept."
The book is a very personal project, but it is not the family album. "I have thought about what these images mean a lot more than I would with casual pictures," Rosie says. Like any other parent, she has lots of photos of Stanley and his younger brother, Victor, 15. "I still find the pictures from before Stanley's diagnosis very difficult to look at," she says.
Some of the portraits taken for her earlier exhibition appear in this book. They show an angelic-looking child with enormous eyes and a deep, soulful gaze. "I guess it is my ignorance that jars," she says as she looks at an 18-month-old Stanley. "I had no idea he was any different. He was an easy baby, so affectionate, joyful and lovely. He's never stopped being lovely, of course, but back then everything was as we expected it to be. I had all the usual hopes and dreams."
Many of the pictures that Rosie believes give the greatest insight into Stanley's life, don't actually feature him. "The whole point is that there is nothing to see. I want to show something that can't be seen. I don't think it's possible to communicate something about autism by photographing individuals on the spectrum alone and it's not necessary to photograph a person to say something about them."
The work is always discreet and respectful, protective of her son's vulnerability. "I couldn't take a picture that felt intrusive or which he wouldn't like." His differences are presented with sensitivity. We learn from an image of burst balloons, a tangled mass of colour and string on a stone floor, for instance, that, unlike most children, Stanley hates having Happy Birthday sung to him.
Carefully framed shots of the natural and built environment convey his preference for playing on the pavement rather than the grass, his love of straight lines and the sensation of running his fingers down windows.
Listing things, says Rosie, is a favourite pastime. Crisp flavours being one of his regulars, the book includes a series of collections of green, blue and red items. There are three buckets on a beach, three plastic mice from the game Mousetrap for instance. Each is accompanied by a caption from Stanley: "Salt and vinegar, cheese and onion, ready salted."
"He has always liked threes too. One day we were walking down the road and he did the flavours again. Later, I saw we had passed some red, green and blue markings on the pavement," says Rosie. "I wanted the book to have a sense of fun."
Stanley is pictured at different ages, and several portraits are taken through glass. "He has always spent time at the window looking out. I like that too," says Rosie. Windows, like camera lenses perhaps, offer a comfortable filter on the world, a chance to freeze a frame. "Maybe there is something about the glass. I don't know if I see differently through it," says Rosie. "Like Stanley, I am a very contemplative person. If I want to think, I often go out for a walk with my camera."
Many of Rosie's pictures are not quite what they seem. A favourite is of Stanley, aged four, sitting on a wooden- framed swing, very still, his eyes cast downwards. The caption explains his need for a clear structure to feel calm and secure. "People might initially see it as a sad picture but I want to confound that. When we go somewhere, Stanley likes to find his space. He is actually serene and happy."
The last picture of Stanley shows him aged 15. Rosie knew the project had run its course. "I didn't want it to go on and on. He is a teenager and quite private. It felt complete. He doesn't always like me photographing him now."
Despite interest from publishers, Rosie decided to self-publish. "It was never about making money, so I would rather be completely in control and not make any money myself rather than let someone else take over, and not make any for me."
With the aid of Twitter, Facebook and support from experts in both autism and photography (the former excited by an original, thoughtful addition to an already sizeable library on the topic), Rosie took to the Kickstarter website, where she has raised enough money to fund a print run.
"When the first copies arrived I was worried what Stanley would think, though I had talked to him about 'our book' and explained that other people would have it in their houses," says Rosie. Stanley agreed to have a look - after he'd had a snack. "He turned all the pages, stopping at the occasional picture. Then he just said, 'Yes, I'm not really interested.' The fact he was so unbothered was a huge relief."
As Stanley grows older, Rosie's focus is on his future. The completion of the book is bittersweet. "Sadly, I am aware - and so is he- that getting older means life is more complicated. These pictures encapsulate some of his happiest times. He feels sad that he can't just run around with other children any more."
People become less accepting, she says. "My wish would be for the person standing next to Stanley at the bus stop to see this book and know that there are people who are different, that it is fine and even beautiful to be different - but it is also not easy. That could make a difference."
• For more information or to buy a copy of the book see understandingstanley.com or rosiebarnes.com
Rosie Barnes: 'Pictures can resonate and stay with you in a way words alone might not.'