TRAILS OF THE SUN
Solargraphy captures cosmic time in a single frame. LAUREN FUGE explores how such a simple technique inspires a sense of connection to the universe.
AS DARKNESS FALLS over the Payette River in central Idaho, Chuck Bueter makes his way along the riverbank to what appears to be an oddly decorated tree. Nine assorted aluminium cans are duct-taped to the slender trunk. They are neither rubbish nor art – these cans are pinhole cameras, and they’ve captured something spectacular about our world that Bueter wants to share.
It is 21 August 2017. A few hours earlier, at 11.28 am Mountain Daylight Time, a total solar eclipse shrouded this part of the US in shadow. A record of the momentous event is curled inside each can on a strip of photographic paper: a solargraph.
Bueter, an amateur astronomer, set up these long-exposure pinhole cameras by the river with the help of local children the previous day. Before sunrise he opened the ‘shutters’ – pieces of tape over the pinholes. “I was the only one up before the Sun; it’s hard to sleep on eclipse morning!” Bueter laughs.
Now, after sunset, Bueter takes down the cans and removes the photographic paper inside. Their images capture the Sun’s movement across the sky from dawn to dusk. Its journey is scrawled on the paper in a bright blazing arc, marked by a fuzzy gap where the Moon has passed in front and blocked its light.
“It’s like Christmas,” Bueter says. “It feels like I’m opening presents.”
One of the nine eclipse solargraphs in particular was “pretty damn cool”. So cool, in fact, that he sent it to NASA, which featured it on the agency’s website as Astronomy Picture of the Day (APOD). Friends and strangers alike wrote to him to express enthusiasm and support. “I got lucky,” he says.
Lucky or not, Bueter’s image is part of a resurging interest in the art and science of solargraphy. Its roots can be traced back to 19th century British photography pioneer William Henry Fox Talbot, the first to record an image on light-sensitive paper.
Patrick Mccauley, a PHD candidate in solar physics at the University of Sydney, says photography has been applied to the Sun almost since it was invented, “and its importance to solar science can’t be understated”.
The specific technique used by Bueter emerged in 2000 in a project called Solaris1, creating solargraphs with pinhole cameras – without lenses – and lightsensitive paper that immediately reveals the image without chemical development.
British filmmakers and keen solargraphers Wendy Bevan-mogg and Austin Capsey explain that using a cylinder for the pinhole camera enables a wide field of of view, “which means in the winter we can capture a complete track of the Sun from sunrise to sunset”.
Since very little light enters the camera, it must be securely attached to a firm place – like a fence or tree – and left for a period that ranges from a day to six months. A day is all you need to capture an eclipse; six months will show you the full extent of the Sun’s changing path through the sky, from a low bump in mid-winter building up to a soaring loop in midsummer. The images are both eerie and beautiful.
“We’re used to the idea of high-speed photography capturing a small transient moment in time, while solargraphy is actually the opposite of that,” Capsey says. It captures “the slow and steady seasonal heartbeat of the Earth”.
The Sun’s differing trajectories reflect the Earth’s orientation as it orbits the star: in winter its axis tilts ‘away’ from the Sun, which therefore follows a low path in the sky; in summer the axis tilt ‘towards’ the Sun, which appears higher in the sky.
Of course, as solar physicist Mccauley notes, solargraphs are not used for cutting-edge research: “For that we use high-resolution telescopes that track the Sun as it moves across the sky, along with nonphotographic instruments like radio telescopes and particle detectors.”
But since pinhole cameras are cheap and easy to make, and only patience is needed to capture a snapshot of cosmic time, solargraphy is a great way to introduce people to the grand scale of our universe and the mathematical dance of the Sun and the Earth.
Bueter, for example, is passionate about using solargraphy to teach his community about astronomy. He began in 2016 for Indiana’s bicentennial celebration, when “there was a big question posed: how do you capture the essence of time?” He turned to solargraphs as a visual way to capture time’s passage, planting cameras atop a baseball stadium, on a flagpole, in parks, outside his barber’s shop, and on the rooftops of a church and several schools.
“I love telling a bunch of kids: ‘Let’s do something dangerous that your parents have told you never to do: let’s look at the Sun!’” Bueter says. “It’s great to start a dialogue with them, to try to eke out what they can discern by looking at a solargraph. We ask them to think about what the lines represent, why the Sun is sometimes high or low, why there might be missing or dotted lines like Morse code, how that might be related to the weather or seasons.”
Bueter also runs workshops on how to make solargraphs. “Each solargraph is unique and personal, which makes it fun for the person doing the investigation,” he says with infectious enthusiasm.
In Britain, Capsey and Bevan-mogg also involve
the public in solargraphy. They have held several exhibitions and workshops, and created a short film about the way solargraphs connect them to the natural world. “To most people solargraphy is a completely new process and genuinely does show people the world in a way they’ve never seen it before,” Capsey says.
Another British photographer, Matt Bigwood, has used solargraphy to explore how to see the world in a different way. First hooked on pinhole photography as a child, he set up pinhole cameras at his daughter’s school to produce ethereal solargraphs.
“The children have all been raised in an instant, digital world,” Bigwood says. He enjoyed showing his daughter’s class a completely different style of photography of the natural world.
On a larger scale, Finnish artist Tarja Trygg ran an international project between 2006 and 2012 to get the public involved in solargraphy, setting up pinhole cameras across the world to record how the Sun’s path changes at different latitudes. The result was a gallery of 300 solargraphs on her website, a short film and a wealth of teaching material. During this period she also teamed up with the European Southern Observatory (ESO) to combine her artistic approach with a scientific point of view. Solargraphs were made over six months at ESO’S telescope sites in Chile.
“Curiosity is a human trait,” Trygg says. “Solargraphy made me interested in the universe and made me see how our planet Earth is a tiny part of a whole.”
Mccauley, whose PHD is focused on solar physics, sees astronomy capturing the public imagination in a way most other sciences don’t. “Astronomy has also taught us that Earth really is a special place,” he says.
This message is central to the work of many solargraphers, who aim to get people talking about the world around them, so perhaps they will take an interest in protecting it.
Bueter wants to promote a culture that embraces solar energy. “When I talk about solar panels I get a lot of pushback from people who just dismissively say that it’s always cloudy here,” he says, “but if they create their own record of the Sun they can quantify how often the Sun shined or not. Evidence is more compelling when it’s evidence that you yourself have derived.” LAUREN FUGE is a freelance science writer based in Adelaide, Australia.
IMAGES 01 Matt Bigwood 02 Chuck Bueter / Nightwise.org 03 Austin Capsey / Wendy Bevan-mogg, Knapp Ridge Films