Solargraphy is a technique for photographing the sun's slow path across the sky as the earth orbits the sun. I first learned of the process in an article about a pinhole camera that was mounted at an observatory in the UK and then forgotten for eight years.
Drawing on the concept of a camera obscura, a pin-sized hole is made in a sealed container lined with light-sensitive paper. The container is mounted securely in the environment and then left for a period of weeks or months to record the scene. Light passes through the tiny aperture and projects an inverted image of the scene on the opposite side of the container, thus creating a paper negative.
Every day, the sun leaves one line on the solargraph. The positions of the lines rise and fall progressively throughout the exposure, from their lowest point at the winter solstice to their highest point at the summer solstice. Stationary objects, such as buildings and tree branches, are also recorded on the solargraph. After exposing the paper negative for the desired amount of time, it is removed from the canister and scanned and inverted into a positive image with the aid of a computer.
Any type of enclosed container can be used as a pinhole camera, and there are plenty of examples online of how to make your own camera for solargraphy. I was thrilled to find this ready-to-use solarcan with a precision drilled pinhole and pre-loaded with photosensitive paper, and promptly bought ten.
The page you are reading now documents my trials and errors with solargraphy.
Solarcan #10145 exposed for 386 days, from 27 February 2021 to 19 March 2022.
This was the first solarcan I deployed. It was mounted on a downpipe off my balcony facing northwest because I overestimated the azimuth of the setting sun. On a future attempt I will try to point the aperture southwest, but I am really happy that I captured the full solar altitude during the summer months. I also like the spots of emulsion that are visible, probably due to rain that splattered inside the camera.
Solarcan #10064 exposed for 381 days, from 28 February 2021 to 15 March 2022
This camera was mounted on the tenth floor of an apartment near Oslo's city center, about a meter in from the edge of the balcony. Opposite the camera is a window reflecting the railing. I love the distortion in this image, which is due to the camera's extreme 160° field of view.
Solarcan #10144 exposed for 371 days, from 7 March 2021 to 12 March 2022
I had the highest hopes for this image. As you can see, the camera was mounted high in a tree with a beautiful view looking south over a belfry. Unfortunately, the paper was sopping wet when I opened the can, and I was unable to recover details in the foreground of the image. The two vertical strips on the image suggest the can was bent during the exposure, but there was no evidence of damage when I harvested it.
Solarcan #10134 exposed for 371 days, from 7 March 2021 to 12 March 2022
This camera was mounted in an apple orchard, and I was surprised that the individual trees are not really visible. The ghosting of the hilltop on the right side of the image suggests that the camera slipped slightly at some point during the year.
Solarcan #10067 exposed for 369 days, from 21 March 2021 to 24 March 2022
My money shot! This camera was mounted on a second floor balcony with an unobstructed south-facing view at about 240 meters above sea level. I could not be happier with how it turned out.
Solarcan #10071 exposed for 207 days, from 17 March 2022 to 9 October 2022
This was mounted over an urban stream looking south into a grove of trees. I suspect that bright streak was caused by a dent in the can when I hung it, but I am pretty happy with result nonetheless.
Solarcan #10046 exposed for 190 days from 24 April 2022 to 30 October 2022.
Like the Apple Chapel above, I had high hopes for this image and ended up being disappointed. I mounted it in the spring on a drain pipe on the side of my father's house. When I picked it up in the fall, the can showed physical signs of sun damage after just six months. Unfortunately, I wasn't able to retrieve very much detail when I scanned the image. I wonder if the intense desert sun coupled with reflected light from house next door over-exposed the paper inside the can?
These are a couple of cameras I deployed around my apartment so I could practice "developing" the solargraphs. I used an old Canon PIXMA MG7150 to scan the paper negatives at 600 dpi. After experimenting with various techniques for manipulating the digital image, I landed on using Photoshop to invert the image and Lightroom for tone and color adjustments.
Solarcan #10117 (south facing) exposed for 116 days, from 29 March 2021 to 22 July 2021
Solarcan #10053 (north facing) exposed for 204 days, from 29 March 2021 to 18 October 2021