Solargraphy is a technique for photographing the sun’s path through the sky by using a pinhole camera to expose photographic paper for anywhere from a few hours to over a year. Photographer Sam Cornwell has created what he believes is the world’s first solargraphy timelapse.
Cornwell is the founder of Solarcan, a unique can pinhole camera that makes it easy for anyone to shoot solargraphs without having to create the pinhole camera themselves.
A “matrix” of 27 Solarcan cameras were installed on the 2018 winter solstice overlooking Williestruther Loch in the Scottish Borders, and all 27 exposures were started at the same time. Cornwell then visited the site once a week until the 2019 summer solstice, retrieving one of the cameras from the matrix (and ending that camera’s exposure) each time.
After the 27 weeks, Cornwell combined all the processed and scanned photos into a grid and a time-lapse showing the path of the Sun moving across the sky from solstice to solstice.
The strange side-by-side overlapping paths seen in the sequence (i.e. in week 3) were due to one or more vandals twisting a can to face a wrong direction.
“It was very difficult to get every Solarcan facing exactly the same direction (to the degree) and as such the original time lapse hopped about a bit,” Cornwell says. “I aligned them all and used content-aware fill in Photoshop to tidy up the edges.
“Perhaps the most surprising thing was how 27 identical sheets of photographic paper all produced different results. The majority were close enough, but some outliers were completely different tones.”
Cornwell says that if he were to re-attempt the project, he would alter the pinhole position to capture the summer solstice, use a stronger mix of materials for the matrix’s frame, and possibly place the project on private land to prevent vandals from affecting the results.