What is a solarigraphy?
The photographs we are making are called solarigraphs, that is, images which record the apparent motion of the Sun in the sky over a certain period of time. In the Time in a Can project, the period of exposure spans six months.
Solarigraphy = (Lensless cam + photographic paper) x 6 months
Why six months?
Six months is the time span between summer and winter solstice. That is, between the moments when the sun reaches its highest and lowest position in the vault of heaven. A solargraph that records this whole period of time leaves a striking image of the solar paths during this six months.
Selecting our participants
We had restricted resources so we established a limit of 40 participants. We selected photographers who had already had experience with lensless photography (some of them a lot) and taking into account their geographical situation on Earth. We wanted to obtain solarigraphs from both hemispheres and also from the ecuatorial line.
Sending out the cameras
We sent to each participant five Time in a Can cameras inside a cardboard tube with some instructions of use. All the cameras had the same technical specifications and were loaded with the same photographic paper.
We asked each participant to place at least one of his/her five cameras pointing in the following direction: South if they were located in the northern hemisphere, North if they were in the South and East if they were near the Ecuator.
One of our aims was to be able to compare how the sun paths were different in the same period of time depending on the viewers latitude. For example, take Tarja Trygg´s solarigraphy taken in Finland with her camera pointing south and compare it with Ross Togashi´s image taken in Hawaii with his camera pointing West. Solarigraphs are unique tools to record the different patterns left by the sun paths.
Receiving and processing the negatives
When the six months of exposure were over, our participants returned the negatives in an opaque envelope back to us at Estudio Redondo in Madrid. There, we scanned and processed them with the same parameters in order to obtain comparable results and an homogeneous series of images.
“The solarigraphic sacrifice”
As strange as it may sound, the technique we use does not need a photographic developer or any other chemicals. With such long exposures, the photosensitive paper is directly darkened by the sun light and the image produced on it can be recorded by scanning it. Of course, the very process of scanning a solarigraphy simultaneously creates a digital image and erases the physical image from the surface of the paper.
So we always made sure our scanning process was working perfectly the first time for every image!!
Recording time and weather
On a solarigraph we not only keep track of the passing months and the latitude of the viewer, but we can also record the weather we ́ve had in that period of time. Just as we can estimate how old a tree was by looking at the rings in its trunk, the trail that the sun leaves in our image tells us, for instance, if we ́ve had some cloudy days, or if the wind has been blowing with intensity at some time of the year.
For example, take a look at the solarigraphs taken during the same six months (June-Dec. 2011) by our photographers Vincent Sellars in Sheffield (United Kingdom) and Kristy Hom in Arizona (USA). We can see how Vincent had a cloudy spring in the UK while Kristy, as expected, did not see much rain in the southwest of the US. Between both, Michal Malkiewicz in Lodz (Poland) seems to have had more rain in winter than in spring.
After receiving all the negatives we have selected one solarigraph from each of our participants. They will be part of the first international Time in a Can solargraphy exhibition! Check out our website regularly for news. We also plan to start a blog with additional infos, images and exhibition details.
In the meantime, you can see the amazing images obtained by our photographers in our gallery.