Solargraphs trace the sun's movement across the sky over a period of months, usually from one solstice to the other.
Jan Koeman, a professional photographer and astronomy enthusiast from the Netherlands, has created dozens of these images using pinhole cameras made out of empty beer cans.
“I read an article about (solargraphy) in a photography magazine ... and I immediately started doing my own experiments,” Koeman said in a phone interview. “I'm always trying to find new locations for the cans to make it more beautiful and more special.”
The resulting images are also an interesting visual record of the weather over the time of the exposure.
On cloudless days, the sun leaves a flawless white streak across the image. On a variable day, the line may appear broken or mottled, and on overcast or rainy days, no lines appear at all.
“It's very interesting to be able to visualize the weather with a simple instrument that costs nothing,” Koeman said.
Koeman recently planted more pinhole cameras. He is looking forward to comparing the fluctuations in the weather in his home province of Zeeland over a period of years.
“As an astronomer, I'm also interested in weather and climate conditions,” he said. “Last year was very strange in the Netherlands because summer was very wet and cloudy, but spring and fall were very sunny and hot. It was completely upside-down and you can see that from the solargraphs.”
How to make a pinhole camera
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