Solargraphy – The art of catching the sun’s path through a pinhole camera

Tarja Trygg, from Finland, is mapping out the paths of the sun all over the world with solargraphs. In her global pinhole project, she sends her small pinhole cameras everywhere around the world to her “can assistants” for sun-path recordings – solargraphy – at several latitudes.

Writer / Tarja Trygg
Photography / Tarja Trygg, Christine Brault

Solargraphs – or solargraphics or solarigraphs – are photographs that people could not have seen before November 2000. This was when these extraordinary images were seen for the first time when the project Solaris [1] published them on the Internet. Solaris was a project initiated by the inventors of this unique photographic technique, Slawomir Decyk, Pawel Kula and Diego Lopez Calvin. They called these kinds of images “solarigraphics”; photographs that come into being within cameras without lenses. Light-sensitive material is exposed in such a way that the image is revealed directly, without the use of further chemical processing. Solarigraphy and heliography[2] refer to a long-exposure photograph that shows the tracks of the sun across the sky. In English, I prefer to use the term “solargraphy” because “solar” means the sun; in my native language Finnish, I use the term “solarigrafia”.

The exposure period of my most famous solargraph was for 180 days in Helsinki. It was displayed in the web gallery of the Solaris project as well.

Solargraph by Tarja Trygg
Fig.1: This solargraph is the result of a six-months exposure with a self-built pinhole camera located on a balcony in Helsinki, in 2002. Solargraph by Tarja Trygg.

This solargraph received considerable public attention and was, for example, published in the respectable daily newspaper Helsingin Sanomat (March 23, 2004; Section Science & Nature). This solargraph has since also spread all over the world via the Internet. In the same year (June 2004), Serbian Photo Magazine REFOTO published this solargraph in the second part of an article[3] about pinhole photography. The issue included three of my solargraphs. In 2005, the original print was exhibited both in Helsinki, Finland, and in Wellington, New Zealand.

Why are so many people amazed by solargraphs?

Solargraphs are unconventional photographs, taken with a pinhole camera. We are not accustomed to seeing these kinds of sun paths with our naked eyes. In the above image, this unique process beautifully captures into a single solargraph the sun’s slow path across the sky each day for six months. The sun reaches its uppermost position during the summer solstice, which occurs in midsummer (June 20, 21 or 22) in the northern hemisphere. Every day, the sun leaves one line on the solargraph, and the positions of the lines rise progressively from December to June. Some lines are not visible because the sun was on those days obscured by clouds.

What do we see in this solargraph in addition to the paths of the sun? First, some islands, the coastline, single trees and a few buildings are clearly visible, as they have stayed stable during the whole exposure period. On the right, in front of the apartment building, ghosts of cars can be discerned in the parking area. Due to the long exposure time, these shapes merged images of several cars that were parked in the same lots on different days.

Despite daily boat traffic in front of the camera, the solargraph does not show any ships, evidently because of their relatively short presence during the total exposure time of the light-sensitive emulsion.

Similarly, one of the most famous early daguerreotypes[4], Boulevard du Temple[5] taken by Louis Jacques Mandé Daguerre (1787–1851) in 1939 in Paris, only shows a shoe polisher working on the street corner whereas all pedestrians have disappeared from the crowded boulevard. In this case, the daguerreotype was exposed for about eight hours during a single day.

Solargraph Daguerre
Fig.2: L.J.M Daguerre, “View of the Boulevard du Temple”, Daguerreotype, Paris, 1839, Stadtmuseum, Munich.[6]

Although people are nowadays used to seeing frozen moments in photographs, the solargraphs, with their extremely long exposure times from days to half a year, appear surprising as they freeze the very slow tracks of the sun into the same image.

Solargraphy — an “anti-technological” means of photographic expression.

In the simplest pinhole camera, the sun will leave traces on an emulsion of photosensitive materials on a piece of black-and-white photographic paper. Solargraphy is an ecological way to take photographs as the solargraphs are neither developed nor fixed in any fluids. All these chemicals would darken the photosensitive emulsion so that the images would eventually disappear. The tracks can be safely viewed only in dimmed light after exposing.
Solargraphy uses a paper negative, which as such is nothing new. In the early history of photography, William Henry Fox Talbot in 1840 invented (and in 1841 patented) a new method to produce the negative-positive process on paper for producing multiple images. Fox Talbot called these kinds of images calotypes or talbotypes (from the Greek kalos, meaning ‘beautiful’).[7] Since photography was still very much a novelty and many people were unfamiliar with the concept, Talbot felt compelled to insert the following note in his book The Pencil of Nature (1844–1846):

“The plates of the present work are impressed by the agency of Light alone, without any aid whatever from the artist’s pencil. They are the sun-pictures themselves, and not, as some persons have imagined, engravings in imitation.”[8]

Solargraphy combines analogue and digital photography. Although a piece of black-and-white photographic paper is inside the pinhole camera, the solargraph is full of colours. It seems magic. Processing the paper negatives forward with the aid of the computer is an exciting and creative act. Solargraphy can provide unusual and fascinating images. You can never be sure what the results will be.

Collaboration with “can assistants” as the key to building a map of solargraphs across different latitudes

I first came into contact with solargraphy and solargraphs in May 2002. I was invited to participate in an international photographic workshop titled PROFILE 2002 in Skoki, Poland. The theme of the workshop was “solarigrafie”. A black curved line on the emulsion of the piece of black-and-white photosensitive material was shown as an example of a new approach to an “anti-technological” means of photographic expression. I was fascinated with this method and began photographing the sun and testing different photographic papers. As I continued to test this method, my fascination increased, like a rolling snowball. I wanted to have solargraphs with up to half a year’s exposure time at different latitudes. The idea of a map of solargraphs came to my mind. But it was not possible to do it alone. I needed some volunteers, and my first camera assistants were my friends, relatives, colleagues and students, as well as people I met at conferences or just about anyone who was willing and interested in my project. The invitation to participate in this global art project – to fill in gaps in the world map of solargraphs – has been open to everybody. The tracks of the sun are different depending on where we stand in the world, and I wanted to see how different they would be. The project became worldwide since the first website[9] went live. The project continued from 2005 to 2016. I have uploaded the most interesting solargraphs on the website My thanks got to all my “can assistants” around the world, including pupils in Scotland, amateur astronomy clubs in California and the Czech Republic, students at Tama Art University, people I have met at conferences, and an array of pinhole photographers; with their help, I have been able to fill in the gaps in the solargraph map.

Fig.3: This solargraph comes from Montréal, Canada (can assistant Christine Brault). The exposure was three months, from June 24th to September 24th, 2007.

My second solargraph example comes from Montréal. It displays several green or blue sun paths on the sky. How did these colours appear into the image? Do they reflect air pollution or the colour temperature of the atmosphere? The white lines came in June during many sunny days. I like this solargraph very much, and my curiosity is in the differences of sun paths across the world. In the northern hemisphere, the sun does not go below the horizon in summer at all and in December, in wintertime, the sun does not go above the horizon. The sun paths are vertical on the equator. It is possible to illustrate how the sun shines at various latitudes during the four seasons during a half year of the exposure. Catching landscapes around the world with the tracks of the sun taken with the aid of the simplest lensless pinhole camera brings a new viewpoint for understanding; it allows us to perceive something in ways that we are not accustomed to seeing with our naked eyes.
To find out more about Solargraphics, read more on or contact Tarja through her projects website.


[1] (The Solaris Project 2000–2002, link no longer working).

[2] (In French, héliographie) is the photographic process invented by Joseph Nicéphore Niépce around 1825. He used this method to make the earliest known permanent photograph from nature (View from the Window at Le Gras, c. 1826). The process used bitumen, as a coating on glass or metal, which hardened with exposure to light. When the plate was washed with oil of lavender, only the hardened image area remained. He called his process “heliography”.

joseph_nicephore_niepce.html (accessed 6 March 2017).


[4] “Photograph on metal, usually consisting of a copper plate covered with a fine layer of silver, giving it the appearance of a mirror. Depending on the angle from which it is viewed, it can appear both negative or positive and is sometimes coloured using pigments…” Bajac (2002:150–51).

[5] (link broken): (accessed 8 March 2017).

[6] (link broken). New links: (accessed 8 March 2017) Note: Taken on December 31, 1837). More information about Daguerre: (link broken).

[7] Quentin Bajac (2002:150): The Invention of Photography. The First Fifty Years. New Horizons. Thames & Hudson Ltd, London.


[9], and the newest website

To find out more about Solargraphics Read more on or contact Tarja through her projects website.

4 thoughts on “Solargraphy – The art of catching the sun’s path through a pinhole camera”

  1. Looks great, Tarja.
    Do you scanned the photopaper? Was are any problem because the paper is still light sensitive?

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