Seasons in the Can
The picture with exposure time of over 11 monthsUsually, taking a picture does not last longer than a split second. More in darker environments, where we need steady hands or risk blurring. In astrophotography, exposures last minutes and even hours.
And then there are photographs with extremely long exposure time. Pictures taking days, weeks and months.
Here's a photo I took over a period of more than 11 months.
Camera obscura#
Not with a regular camera, of course. I used something called a pinhole camera. One of the oldest and most simple cameras. A camera without any lens. The setup is extremely simple, albeit not so easy to understand.
It's all about a hole, which needs to be tiny. Ambient light, reflected from the surroundings, passes through the tiny aperture and projects an image on a surface opposite to it. The size of the projection depends on the distance between the pinhole and the surface. Some are large; you can walk into a pitch-black room and, after adjusting your eyes, marvel at a dim, spooky projection of the outside world forming on a big wall. That setting is familiar as camera obscura. Scaled down to a small light-proof box with a pin-sized hole on one side and a piece of photographic paper instead of a projection screen, it's called a pinhole camera.
The image is flipped both horizontally and vertically. It's easy to see why: the light rays that enter from the right side end up on the left one, the ones coming from above hit the bottom of the screen... you get the (inverted) picture! The tiny aperture is crucial because it prevents the light from scattering the way it does when it enters a room through a window.
This principle is fundamental in the physics of optics and is also the basis for how traditional photographic cameras work. In fact, this is also fundamental to working of our eyes. Fun fact: the projections forming on the retina of your eye are also flipped upside down and sideways, but your brain has learned to
Solarcan#
Back in 2017 I supported a lovely little project at Kickstarter called Solarcan (https://solarcan.co.uk/). The funding was successful and the people behind it produced a neat contraption. Basically an aluminium can we tend to associate with fizzy drinks, albeit with a light-sensitive paper on the inside and a tiny perforation in the shell. It was one of these ready-made pinhole cameras that I strapped to the rainpipe at the balcony of our house on Sunday, April 2, 2023. Then I pretty much forgot about it. Which is an important step. Shutter clicks lasting many months need a lot of patience.
Almost a year later, on Sunday, March 10, 2024, I took it off with the help of my kids. We opened the can and took put the photographic paper. It looked dirty yellow, with streaks of dark lines. We quickly scanned the image before it decayed. Flipped it both horizontally and vertically. The last and crucial step to do was inversion. Kind of like what we used to do when making a paper photograph from a negative, but through a quick operation in Photoshop. That is when the moment of magic happened...
Sun - Seasons - Weather - Time#
You can see all of that in one picture!
The tiny hole was pointed roughly southward in hope to capture the Sun. At the bottom, we see dark silhouettes of the houses across from our garden. But above them, indeed, a curtain of elegant curved lines. Every one of them a apparent path of our star, east to west across the sky above Brussels.
We can clearly see the lowest point at the time of the winter solstice. At the time of the summer solstice the Sun was so high that it escaped the picture frame.
But note that the Sun paths are not continuous; they get interrupted frequently, forming randomly intermittend lines. I would think that must be the influence of clouds dimming the incoming light! Yes, of course also planes and birds and flies sitting across the pinhole :-) But mostly clouds, and you can even kind of grok which days and even weeks were cloudier than other ones.
The picture also reveals the darkest part of the year. The paths got more and more flat in the autumn, up to the point at the end of December when the Sun barely got up at all for the day. After that the curves started to grow again, adding to the luminosity of the autumn ones. So it happened that the gloomiest months of the year got painted double, and therefore, ironically, shite more brightly than the rest.
And of course, we also see the time. And a clockwork of celestial mechanics making a drawing on a paper in a can. Quite surreal.
- https://en.wikipedia.org/wiki/Pinhole_camera
- https://en.wikipedia.org/wiki/Camera_obscura
- https://solarcan.co.uk/
ENGLISH ARTICLEOCTOBER 20, 2018 AT 01:46:40 UTC