Just check out that image, called ‘Solargraph’. It is from the UK, taken of Bristol’s Clifton Suspension Bridge. The lines are the travel of the sun over time, showing the motion of the earth relative to the sun, as well as periods where no sun at all was visible.
According to Wired, photographer Justin Quinnell made the images:
from the simplest of cameras: a soda-can with a 2.5mm hole punched into the metal and a sheet of photographic paper hidden inside. Because photo-paper is so much less sensitive to light (in the darkroom you’d typically expose for 10-seconds or more), it needs to sit around for a long time to record an image.
How long? The image took 6 months to collect, during which time the project changed shape according to HouseholdName:
Quinnell, a renowned pin-hole camera artist, says the photograph took on a personal resonance after his father passed away on April 13–halfway through the exposure. He says the picture allows him to pinpoint the exact location of the sun in the sky at the moment of his father passing.
Looking further into the pinhole camera,notes:
A pinhole camera goes a step further than a camera obscura. By using film, it records the projected image for posterity. Its chief drawback, of course, is that it doesn’t admit very much light—several thousand times less than a lens an inch wide—so you must wait patiently as enough accumulates on the film to make a picture. On the other hand, the image stays in focus no matter how far you place the film from the aperture (though “focus” is a relative term in pinhole photography; an image projected through even a tiny pinhole is never as sharp as one focused by a decent lens).
Here is an schematic of a basic pinhole camera:
Definitely head over to Justin Quinnell’s site to see the rest of the photos from that set as well as a number of other cool images and links to some other great pinhole artists!